GUANGDONG'S Public Security Bureau has vowed to find through 'every possible means' the criminals involved in a record 14 million yuan (HK$13.02 million) hijack in boomtown Panyu. Bureau director Chen Shaoji is leading the investigation into the crime, which is said to have shocked the central Government. Hong Kong immigration authorities have been asked to watch out for at least four armed robbers who hijacked a security van and made off with the cash on Friday. An official at Mr Chen's office yesterday said he had gone to Panyu to take command but declined to give further details. A spokesman for the bureau said it would bring the criminals to justice through 'every possible means'. He said police had already collected 'important clues'. The hijack took place at 8 am on Friday at the Yifa Shopping Plaza in Panyu, midway between Guangzhou and Hong Kong. At least four men reportedly ambushed a security van parked outside the local branch of the Agricultural Bank of China as the guards were transferring the money. The Beijing-backed Wen Wei Po said at least one security guard had been shot and injured but other unconfirmed reports said two people were killed. It was not clear if they were the raiders or guards. A total of seven shots were said to have been fired. The robbers were believed to have escaped with the equivalent of 14 million yuan in cash - including about $2 million in Hong Kong currency. Witnesses said the robbers had driven the van south onto the Guangzhou-Zhuhai Highway. The van had not been recovered last night. Police armed with AK-47 rifles and wearing bulletproof vests were still guarding major highways near Panyu yesterday, searching suspect vehicles. Bank officials declined to comment yesterday. Hong Kong immigration authorities said mainland authorities had asked them to keep a close watch on the border. 'We have been on alert after having been informed by the Chinese side but we do not expect any delays for people departing or entering through Lowu,' said Lowu chief immigration officer Tse Sai-kit. 'Our main concern, besides security, is cross-border service. We cannot simply sacrifice travellers' interests,' Mr Tse said. Mainland authorities are expected to seek the help of the local police to ensure the robbers do not enter Hong Kong.