An explosion of questions
'A loving husband, sincere and honest' was how neighbours characterised Zhao Dengyong So it came as a shock when the 26-year-old was blamed for a suicide bombing last month.
Four people, including the alleged suicide bomber, were killed and 16 others injured in the attack on a county office in Qiaojia county, Yunnan province, on May 10.
Residents and internet users asked what could have driven the young man, who appeared to have no connection to the office, to leave behind his wife and son and undertake the assault.
'Zhao Dengyong was an outsider seeking odd jobs here,' said a neighbour, 65, who declined to be named. 'He had no enemies and didn't harbour any hostile feelings towards the government. He also had no land in this county. Why would he blow up [the office]?'
The local government is facing a credibility crisis, as a sceptical public question a series of conflicting official findings.
One question concerns Zhao's alleged culpability in the attack - on a community office used to process relocation agreements.
'Beijing should send forensic and criminal investigators to uncover the truth that the local government has buried,' said the elderly neighbour.
Zhao's older brother, Zhao Dengxian, also questioned the findings and insisted that his brother was being used as a scapegoat. 'They accused my brother of the suicide bombing, and yet they can't even track the source of the bomb. How can you convince people with that?' he said.
Professor Zhan Jiang, a communications lecturer at Beijing Foreign Studies University, said the public's scepticism was no surprise, given people's lack of confidence in government announcements. 'It's difficult to say who's right and who's wrong,' Zhan said. 'But it's very difficult to cover things up these days.'
The blast occurred shortly after 9am in the Huaqiao community office in Baihetan town in the centre of Qiaojia county.
The next day, May 11, the local government said Zhao, who was not from the area, was responsible.
Grainy surveillance footage shows a man, carrying a black backpack, walking into the office. Minutes later, there is an explosion.
Witnesses said it was a hot morning and many people had arrived early at the office to sign relocation agreements. That's because May 10 was the deadline for registering for a new home on the outskirts of Baihetan, where most relocated residents were being sent.
In all, more than 7,000 villagers were facing relocation for various reasons, including urban renewal and the expansion of shopping areas.
Xiong Shunjin, 37, is among the few survivors. His left arm is covered in severe burns, and his lower back was injured by human bone fragments. 'I had just arrived at the scene, and three minutes later it exploded. There was no time to run. I was very scared,' Xiong said.
Another surviving villager, Li Weiyou, 42, lost his 35-year-old wife, Ren Yi , in the attack. They had been married 12 years, and have an 11-year-old son. Li said he did not see anyone who looked like Zhao walk into the community office.
'I was there at around 8.40am with my family members,' he said. 'There was no fighting or quarrelling or any indication that an explosion might occur.
'I was standing by an office desk when suddenly the blast went off. The next thing I knew, my face was covered in blood and I had lost my hearing. The bomb exploded under an office desk a few metres from me ... there were about a dozen villagers in the office and four officials. They all went down.
'I saw my sister-in-law, who was carrying a baby at the time, lying on the floor. Then I realised my wife was also down.
'Her body was covered in blood and both her arms were burned. She couldn't speak, but she was looking at me, gasping for help.'
The son of Li's brother-in-law, Tang Tianrong , also died.
Outside the office, Li saw an arm and leg on the ground. Pictures posted online showed bloodstained office walls, broken glass and other debris.
The authorities said Ren, Tang, Zhao, and a demolition official who died in hospital lost their lives in the incident.
On the day of the attack, Xinhua quoted a Kunming newspaper as saying that a woman had set off the blast at the community office after being asked to sign a home-relocation agreement.
But the next day, Xinhua quoted the county's police chief as saying that the surveillance footage showed that Zhao was the bomber.
Police even gave his address in the town of Baogunao, about 140 kilometres away.
On the same day, county police showed the security footage to Xinhua and the People's Daily. They reported that Zhao had messy hair, wore multiple layers of clothing, and carried a backpack as he approached the community office. He lingered in the outdoor courtyard for about four minutes and then went inside.
A spokesman for the Yunnan provincial public security bureau told state media that Zhao's multiple layers of clothing were abnormal, given the hot weather. He also speculated that Zhao's backpack 'might have been carrying explosives'.
Authorities said DNA collected at the scene matched Zhao's, and that his parents and wife had identified his remains.
However, the authorities have yet to say what Zhao may have had for the attack. Citing ongoing investigations, they refuse to release the security footage to the public.
But that has not stopped the authorities making accusations against Zhao. For example, Fang Zonghui , party secretary of Qiaojia county, told Xinhua that Zhao was an extremist, sociopath and a pessimist. Zhao, Fang claimed, bore a hatred of society.
Even so, some neighbours said they saw Zhao on the eve of the bombing helping local traffic police unload carry confiscated unlicensed motorcycles from a police truck.
Zhao had been living in Baihetan for three years, and he worked odd jobs such as that for the traffic police. He earned about 100 yuan (HK$122) to 120 yuan during the day, and drove a motorcycle taxi at night.
Near the outskirts of Baihetan, Zhao rented a room with a shared courtyard bathroom and kitchen for 85 yuan a month. The 15 square metre property is tucked down a dirt alley.
Inside Zhao's home, the South China Morning Post saw a copy of his photo identification and registration booklet with the local Communist Youth League lying on the floor.
A green uniform was hanging on a wall and a pair of military-type shoulder rank insignia could be seen on his bed. They suggest that Zhao was a non-commissioned officer in the armed police.
A jar of chilli paste and a greased wok were left out in the open, alongside two sets of chopsticks and bowls on a small table.
Various metallic tools, a pair of women's shoes, toys and books - about prenatal care, advanced Chinese chess strategies, and motorcycle maintenance - were strewn on the floor.
Zhao's landlord, Peng Zixiang , 51, described him as an avid Chinese chess player and a loving husband with no vices. 'He and his brother used to stay up until 2am playing chess,' Peng said. 'Zhao never used to go out much at night; he played songs on his mobile phone for his wife and nearly two-year-old son.
'He didn't drink, smoke or gamble. In the last three years, I have never once heard him yell at his wife or their infant boy.
'He didn't socialise much with others, but he was surely a sincere and honest man.'
Peng said the only issue he ever had with his tenant was that Zhao was occasionally short on the rent.
Peng also said that Zhao had recently traded in his old motorcycle for a new one that cost him 2,000 yuan. 'I never saw him carrying a backpack,' Peng said.
To strengthen their case against Zhao, the authorities released what they said was an entry from Zhao's online journal, dated May 2, 2010.
It said: 'Society's cruelty is making me explode. I don't know how many will die at my hands when I can't make a living any more. Ability decides nothing, social background decides everything.'
A separate diary entry, which police said Zhao had written while he was a high school student, said: 'My life has gone in the wrong direction, leaving a hole in my heart. At times, there are extreme and unhealthy thoughts, but I've made it through.'
Police also claimed to have uncovered part of an online diary entry from Zhao's wife, Zeng Jianhua , saying she felt heartbroken after an unspecified quarrel with Zhao. However, in an interview that ran in the Southern People's Weekly a week after the bombing, Zeng said she did not recall writing the purported entry. She said her relationship with Zhao had always been good.
'No matter what, he would never have done something like this,' Zeng was quoted as saying, adding that Zhao had never owned a backpack.
Besides failing to establish a possible motive for the attack, police have also been unable to determine where the bomb or backpack originated, nor have they been able to say what Zhao was up to in the hours before the explosion.
Within three days of the blast, local and state media quoted Qiaojia police chief Yang Zhaobang as saying that at least 25 experts had conducted a thorough investigation of the crime scene. Yang said he would bet his career on Zhao being the bomber.
A preliminary investigation has determined that the bomb was probably made of ammonium nitrate, an odourless chemical commonly used as fertiliser and in home-made bombs.
A few days after the blast, the South China Morning Post reported that black-market explosives and guns were being openly advertised in the remote and mountainous area.
Small, handwritten ads could be seen on the streets of Qiaojia, an area known for its mining and quarry activities. The county is on the Jinsha (Yangtze) River, on the border with Sichuan province.
Most advertisers claim they can arrange delivery by car within an hour in central Kunming, the provincial capital, with guns delivered outside supermarkets and post offices. Some advertisers also said they had delivery networks in remote counties. 'We have people in Qiaojia, Dongchuan and Huize, but the headquarters are in Kunming,' a dealer said by phone.
Police in Qiaojia declined to comment on the ads. But to highlight the scale of the problem, Yunnan police launched a massive campaign in February, offering rewards of up to 1,000 yuan for tips leading to the seizure of explosives or weapons.
Purported arms dealers that the South China Morning Post contacted said 240 grams of military-grade explosives would cost 600 yuan, but 24 kilograms of black powder explosives - generally used for mining and quarrying - cost just 500 yuan.
The ease with which such explosives can be obtained may help shine some light on how rural residents have been able to set off explosions in protests over illegal or unfair land grabs in recent years.
On the internet, microbloggers are still befuddled by the attack. They are questioning which version of events to believe, and also wonder if the authorities fabricated evidence. 'Why are they still withholding the surveillance tape from Zhao's family and the public?' wrote a microblogger. 'Something fishy is going on.'
Zhao Dengyong's home village was this far from the blast scene
- Authorities have not said what motive he may have had