Chinese mineworkers in southern Pakistan were targeted by a suicide bomber today in what is believed to be part of the Islamist backlash which has killed more than 140 people in the last week.

A suicide bomber rammed a car packed with explosives into a convoy of police vehicles escorting the Chinese technicians through a busy street in the southern town of Hub.

The Chinese were unhurt but the massive explosion killed 29 Pakistanis, including seven police officers travelling in the van that was rammed. The fronts were blown off roadside shops, and witnesses described body parts littering the street. None of the Chinese workers was hurt.

"(Islamabad's close alliance with China) is a vital relation for Pakistan but it appears that somebody wants to damage it," foreign office spokeswoman Tasnim Aslam told the AFP news agency.

Today's attack in Hub is puzzling government security analysts, as it is the first attack since the fall of the Red Mosque to take place in the south of Pakistan. The Government has been facing a nationalist insurgency there, not from Islamic extremists, but from Baluch tribal leaders trying to win more autonomy and a greater share of the wealth from the region's natural gas resources.

Zahid Hussain, Times correspondent in Islamabad, said that the Baluch tribes had never previously resorted to suicide bombings and that the attack appeared to carry the hallmarks of Islamic extremism.

The choice of target also appeared to point to Islamists, Hussain said. Beijing was a close and valued ally of the Pakistan Government, which last year handed back to China one of the leaders of the Muslim insurgency in China who had taken refuge in a Pakistan tribal area.

"It is one possible theory that Islamic extremists in Pakistan are making common cause with the Muslim insurgency in China," said Hussein. "Otherwise there would seem to be no reason for it."

Chinese workers have previously been the targets of both the Baluch insurgents in the south and the Islamic extremists further north. In February last year, three Chinese engineers were gunned down in Baluchistan, where they were working for a cement plant.

One of the incidents that led government forces to lay siege to the Red Mosque was when Islamic extremists from the mosque raided a massage parlour in Islamabad and took hostage seven or eight Chinese women who had been working there, claiming that they were prostitutes and the premises were a brothel.

Then, two weeks ago, suspected Islamic militants shot dead three Chinese men in the northwestern city of Peshawar, prompting China to demand better protection for its citizens.

The heavy police protection around the mineworkers' convoy was the reason why none of the Chinese was hurt in the attack, which also injured a further 30 people, some of them critically.

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