GENEVA (AP) — A U.N. panel urged the Chinese government on Friday to apologize to the victims of its crackdown on pro-democracy activists in Tiananmen Square 19 years ago.

The Geneva-based Committee against Torture said China should carry out a "full and impartial" investigation into what happened in June 1989, when the military attacked student demonstrators. Hundreds were thought to be killed, but most of the deaths were away from the square.

China also should "provide information on persons who are still detained from that period, inform the family members of their findings, offer apologies and reparation as appropriate and prosecute those found responsible for excessive use of force, torture and other ill-treatment," the 10-member panel said.

Last year, the U.S. State Department said that between 10 and 200 Tiananmen activists were estimated to still be in prison.

In a 15-page report released Friday, the U.N. committee appeared to deliver its strongest criticism yet of past and present incidents of torture in China. It was the fourth time the country has appeared before the Geneva-based panel.

Earlier this month Li Baodong, China's ambassador to the United Nations in Geneva, told a public hearing that his government had "zero tolerance for torture" and was making progress in stamping out abuse.

But the committee members said it was "deeply concerned about the continued allegations, corroborated by numerous Chinese legal sources, of the routine and widespread use of torture and ill-treatment of suspects in police custody, especially to extract confessions or information to be used in criminal proceedings."

While acknowledging that China has made an effort to outlaw torture in some instances, the panel said Beijing still had to do more to meet its obligations under the 1984 U.N. Convention Against Torture.

The panel urged Beijing to abolish all forms of forced labor, which are imposed for minor crimes and often without trial. China should also stop the use of "secret prisons" and the harassment of lawyers and human rights campaigners who highlight abuses, and investigate the March crackdown on anti-government forces in Tibet during which exile groups say at least 140 people were killed and more than 1,000 were detained, the panel said.

The Chinese mission in Geneva had closed for the day Friday when the report was issued and telephone calls from The Associated Press were not answered there.