BAGHDAD: Inmates at Abu Ghraib prison started a fire and attacked guards, prompting authorities to call in Iraqi troops and American helicopters for support, the US military said Friday.

The unrest began when three inmates started a fire in their cell Thursday and tried to overpower guards in an apparent escape attempt, US military spokesman Master Sgt. Nicholas Conner said.

Prison authorities called in the Iraqi military to help quell the disturbance inside, while the US provided helicopter support to monitor areas outside the prison, Conner said.

Iraqi authorities reported that three Iraqi guards and three prisoners were injured before security forces regained control, Conner said.

An Iraqi lawmaker said, however, that two prisoners were killed Thursday and that violence had broken out again on Friday.

Shatha Al-Abousi, who is a member of Parliament’s Human Rights Committee, said prisoners had managed to get an assault rifle and were demanding that they be pardoned.

Al-Abousi said a delegation from the Human Rights Ministry was in negotiations with the prisoners to try and get them to stand down. She did not have any further details.

The US military said it had not been called again to help on Friday.

The prison, notorious since the 2004 release of photos showing US soldiers abusing prisoners, is now back under Iraqi control. Eleven US soldiers were eventually convicted of crimes at the prison.

Local media reported that the Iraqi security forces fired shots during the riot and that an unspecified number of inmates were killed, but Deputy Justice Minister Busho Ibrahim said there were no fatalities.

Local reports on the incident varied widely. One said the disturbance was a clash between Sunni and Shiite inmates, while another said it was an organized protest by inmates demanding to be allowed to use cell phones.

Lawmakers from a political bloc loyal to Shiite leader Moqtada Sadr said they had information that the unrest was sparked by inhumane treatment of inmates by the prison administration. They also called for an investigation into the incident and said they would bring it up before Parliament.

“We will not let this incident at Abu Ghraib prison pass peacefully,” said spokesman Ahmed Al-Masoudi in a statement on the bloc’s website.