A Jordanian citizen died after being beaten by police, the second time this week, a police spokesman said Sunday, casting a rare spotlight on the nation's U.S.-trained security forces, that may also have worked as proxy jailers for the CIA.

The deaths have provoked angry demonstrations in this stable U.S.-ally. Jordan has largely escaped the reputation for human rights abuses that clings to many of its neighbors.

Fakhri Kreishan, 47, died late Saturday, two days after slipping into a coma caused by a severe beating to the head that took place during a clash between police and residents in the southern city of Maan.

Sadem al-Saud, 20, died last Sunday, three weeks after he was put into a coma by a beating administered during an interrogation in an Amman police station.

Labib Kamhawi, a leading human rights activist, said Jordan has "always been a security-oriented state."

"That's why the mentality of police forces is programmed to use excessive force against anything it deems a hazard to national security," he said.

Last year, the New York-based Human Rights Watch accused Jordan of systematic torture in some detention facilities — something Jordan has denied.

Police spokesman Maj. Mohammed al-Khatib said the six officers suspected of beating Kreishan and al-Saud have been arrested and will be tried in a police court. He said neither of the deceased were wanted by police.

The quick police acknowledgment of the deaths and prosecution of the perpetrators were apparently in response to government fears the news would provoke further demonstrations around the country.

In Maan, violent riots erupted shortly after Kreishan's death. Angry protesters torched a police vehicle and a security booth after opening fire on the policemen manning the station in the city, said eyewitness Mohammed Anani, a resident of Maan, 135 miles south of the Jordanian capital.

Dozens of young men also clashed with police and blocked the desert highway leading to the Red Sea port of Aqaba before calm was restored, Anani said in a telephone interview.

"People are angry at police brutality," he said.

It is unusual for Jordanians to criticize their security apparatus, which has been a long-standing symbol of national pride.

Pro-government lawmaker Mamdouh Abbadi warned that the government "must severely punish the perpetrators for their crimes and announce the findings of the police investigation, or parliament will take action."

Jordanian security forces had a major role in the U.S.-led global war on terrorism, including assisting Washington in its hunt for Al Qaeda in Iraq leader Abu Musab al-Zarqawi, who was killed in a U.S. air strike in neighboring Iraq in 2006.

Jordan has also purportedly served as a proxy jailer for the CIA until at least 2004, according to Human Rights Watch. The group said that the CIA transferred at least 14 terror suspects to the kingdom for interrogation after the Sept. 11, 2001 attacks. Jordan has denied the charge.

Malcolm Smart, regional director for the London-based Amnesty International, said this week's deaths were a "serious development."

"This kind of force cannot be tolerated," he said, adding that the responsible officers must be prosecuted and suspended from the service.