ISLAMABAD, Pakistan — Pakistani troops raided Islamabad's Red Mosque today and attempted to flush out the remaining militants entrenched inside a women's religious school in fierce fighting that left at least 50 militants and eight soldiers dead, the army said.

The troops stormed the mosque compound before dawn. More than 12 hours later, they were still trying to root out the well-armed defenders said to be holding a number of hostages. Officials said at least 50 women were allowed to go free from the complex. Some 26 children had earlier escaped.

Clashes this month between security forces and supporters of the mosque's hardline clerics prompted the siege. The religious extremists had been trying to impose Taliban-style morality in the capital through a six-month campaign of kidnappings and threats. At least 80 people have been killed since July 3.

The assault began minutes after a delegation led by a former prime minister left the area declaring that efforts to negotiate a peaceful end to a week-old siege had failed.

A senior civilian official said troops had arrested dozens of people inside the compound and that part of the madrassa had caught fire.

Today's attack followed a botched commando raid on the high-walled mosque compound over the weekend.

BEIJING — China executed the former head of its food and drug watchdog today for approving untested medicine in exchange for cash, the strongest signal yet from Beijing that it is serious about tackling its product safety crisis.The execution of former State Food and Drug Administration director Zheng Xiaoyu was confirmed by state television and the official Xinhua News Agency.During Zheng's tenure from 1998 to 2005, his agency approved six medicines that turned out to be fake, and the drugmakers used falsified documents to apply for approvals, according to previous state media reports. One antibiotic caused the deaths of at least 10 people."The few corrupt officials of the SFDA are the shame of the whole system and their scandals have revealed some very serious problems," agency spokeswoman Yan Jiangying said at a news conference held to highlight efforts to improve China's track record on food and drug safety.Zheng, 63, was convicted of taking cash and gifts worth $832,000 when he was in charge of the State Food and Drug Administration.His death sentence was unusually heavy even for China, believed to carry out more court-ordered executions than all other nations combined, and indicates the leadership's determination to confront the country's dire product safety record.Fears abroad over Chinese-made products were sparked last year by the deaths of dozens of people in Panama who took medicine contaminated with diethylene glycol imported from China. It was passed off as harmless glycerin.