In a separate scandal, Chen Bingcai, a former official at the State Administration of Foreign Exchange, accused the museum on his qq.com microblog of evading tax on ticket revenues from exhibitions held outside the Palace Museum. He said tickets for those exhibitions were not formal tickets authorised by the tax authorities, suggesting the exhibition operators tried to pocket the revenue without paying tax.

The Palace Museum officials said that the National Museum of China, also on Tiananmen Square, was responsible for those exhibitions and that the Forbidden City had nothing to do with them, a claim denied by the National Museum.

Earlier this month, the Palace Museum officials who manage the Forbidden City had to endure humiliating accusations that have undermined decades of public faith in their ability and integrity.

On August 8, the museum denied that it had sold five letters dating back to the Song dynasty (960-1279) in 2005, saying it had never actually bought them in 1997, China Youth Daily reported.

On August 10, museum officials denied that a Qing dynasty (1644-1911) wooden screen had been soaked in water. However, the Caixin Online news portal quoted an unnamed insider as saying that officials had told a meeting that a burst water pipe had drenched the screen but that no damage was evident after it had been left to dry in the shade.

Also on August 10, a museum spokesman denied week-old allegations by blogger Long Can, a former reporter from Chengdu, Sichuan, that there had been four accidents involving valuable relics.

Rather than being heavily guarded and impregnable to burglars, the museum has been shown to be careless in its handling of cultural relics and prone to cover-ups.

This month's woes follow the breaking of a 1,000-year-old Song dynasty porcelain plate into six pieces on July 4 - something not reported to authorities for 27 days.

In May, seven precious powder compacts and cases on loan from a Hong Kong museum were stolen by a jobless man. Police have yet to retrieve some of the items.

When museum officials sent a banner to the municipal Public Security Bureau to thank officers for catching the thief it mistakenly read 'Shake the motherland's prosperity' instead of 'Protect the motherland's prosperity'.

Officials initially denied using the wrong word and then blamed the museum's security department for the mistake.

Also in May, China Central Television anchorman Rui Chenggang wrote on his microblog that museum officials had been renting out the Jianfu Palace Hall as an exclusive private club for billionaires. The museum denied the accusation before admitting that decisions regarding the club had been made by a subsidiary, with the museum's administration kept in the dark about commercial activities in the hall.

These embarrassments have shed light on security loopholes and mismanagement, prompting some observers to say that the nation's cultural heritage has been degraded by inept management and commercialisation, and that the crown jewels of Chinese cultural heritage have been placed the wrong hands.

'I am extremely concerned about the ability of such uncultured people to properly preserve and safeguard precious cultural assets,' wrote one internet user. 'The scandals have destroyed the confidence people previously had in the museum as the guardian of Chinese culture.'

The five-century-old Forbidden City, in the centre of Beijing, served as an imperial palace from the Ming dynasty (1368-1644) to the end of the Qing. The Palace Museum now houses 1.5 million cultural relics.

Even though the Kuomintang removed more than 655,000 artefacts from Beijing in the 1930s to prevent them from falling into the hands of invading Japanese troops, eventually taking them to Taipei, the Unesco World Heritage Site is not just another museum to Chinese, but a sacred place housing the best of traditional Chinese culture.

Archaeologist Liu Qingzhu, a former director of the Institute of Archaeology at the Chinese Academy of Social Sciences, said the museum had been regarded as 'the apex of a pyramid' of culture.

Professor Zhu Dake, a cultural critic at Shanghai's Tongji University, said the Forbidden City, as China's main surviving cultural symbol amid the decline of traditional heritage, the loss of relics during the Cultural Revolution and rapid modernisation, was 'an isolated island in the middle of a flood'.

'People are very disappointed as they had too high an expectation of the museum as being a rare survivor of tradition,' Zhu said. 'They are disappointed by the deteriorating cultural situation in the country.'

Li Bochun, whose Chinese Cultural Renaissance Institute promotes traditional Chinese culture, said sloppy management of cultural relics stemmed from a lack of responsibility and too much focus on money.

'Many management staff lack a certain kind of morality and the skills to handle relics, and merely pursue profits,' Li said. 'It's a result of decades of development focused on the economy and the neglect of cultural and spiritual education.'

Other analysts said the lack of effective scrutiny under the mainland's political system was the deeper reason for all the scandals.

'The abuse of power is the reason for the loss of a bottom line in law, morality and culture,' Zhu said. 'As long as the system stays the same, with no properly implemented independent scrutiny, we can tackle the problem only when it hurts. These problems will recur.'

The management style left it open to corruption, he said, because the museum was 'a reflection of the corruption in a wider scope of government agencies'.

Lu Guoping, a Shanghai-based columnist, said such scandals were inevitable. 'It's definitely not some coincidence or a temporary problem. Under the current system, it's impossible to cure completely. Scrutiny is only effective when it's conducted by independent non-governmental organisations, because there is no direct conflict of interests.'

Internet users are not only furious about the museum's mistakes but also the way it handled them after they were exposed: covering up and shifting responsibility. Apart from denying allegations, museum officials have done little to effectively restore public trust.

Everyone made mistakes, Zhu said, but the key was how one reacted to them. The Chinese bureaucratic system had a habit of denying mistakes and stifling dissent.

The exposed problems were 'the tip of the iceberg', he said, and that 'all this media exposure of problems at the museum - under the same system - won't change a thing.'

Liu said the only way to correct serious mistakes was to be honest and tell the truth. Many of the scandals were originally exposed on microblog platforms and when an institution became the focus of attention, internet users would continue digging and posting leads online.

Liu Deqian, the deputy director of the Chinese Academy of Social Sciences' Tourism Research Centre, said that media exposure of mismanagement might help improve transparency and accountability at the museum. 'For a huge institution like the Palace Museum, which has been rarely criticised before, it is unprecedented.'

72ha

The area covered by the Forbidden City, the world's largest surviving palace complex. It was built between 1406 and 1420