Victims' families and witnesses on Tuesday accused Iraqi Vice President Tareq al-Hashemi of masterminding killings at the opening of his trial in absentia on charges he says are politically-motivated.

Hashemi, one of the country's top Sunni Arab officials, was accused in December of running a death squad and, along with his staff and bodyguards, faces around 150 charges.

The vice president, last known to be in Turkey, is the subject of an Interpol red notice calling for his arrest.

The Central Criminal Court of Iraq opened the case Tuesday morning after a two-week delay over a venue dispute, and heard testimony from families of three victims whose deaths Hashemi is accused of orchestrating, according to an AFP journalist in the courtroom.

Three other witnesses gave testimony, accusing Hashemi of masterminding the assassinations, before reporters were led out of the room. Neither Hashemi nor any of his staff were present in court.

Thursday's hearing was tackling the murders of two security officials and a lawyer.

The charges against Hashemi were first levelled in December after US troops completed their withdrawal, sparking a political crisis that saw the vice president's bloc boycott cabinet and parliament over accusations Shiite Prime Minister Nuri al-Maliki was monopolising power.

Hashemi and his political allies have slammed the charges as targeting their Sunni Arab-backed Iraqiya bloc, which won the most seats in March 2010 parliamentary elections but was outmanoeuvred for the premiership by Maliki's alliance.

After the initial charges were filed, the vice president fled to the autonomous Kurdistan region in northern Iraq, whose authorities declined to hand him over to the central government.

They then allowed him to leave on a tour of the region that has taken him to Qatar, Saudi Arabia and now Turkey. Ankara has said it will not extradite him to Iraq.

Iraq 'torture prison' still open: HRW
Baghdad (AFP) May 15, 2012 - Iraq is still holding prisoners at a detention facility that has been at the centre of torture allegations despite Baghdad having said it closed it a year ago, Human Rights Watch claimed on Tuesday.

The New York-based rights group called for Baghdad to start an independent investigation into allegations of torture and mistreatment, as well as other issues, at Camp Honor and other jails.

"Iraqi security forces are grabbing people outside of the law, without trial or known charges, and hiding them away in incommunicado sites," Joe Stork, HRW's deputy Middle East director, said in a statement released by the rights group.

"The Iraqi government should immediately reveal the names and locations of all detainees, promptly free those not charged with crimes, and bring those facing charges before an independent judicial authority."

HRW said 14 officials, lawyers and detainees it interviewed said individuals had been held recently at Camp Honor, the apparent closure of which was announced by Justice Minister Hassan al-Shammari in March 2011.

It also said judicial investigators were still carrying out interrogations at the facility.

Previous to that announcement, The Los Angeles Times reported that prisoners were kept under harsh conditions at Camp Honor, a detention facility in the defence ministry complex in Baghdad's heavily-fortified Green Zone, sometimes for up to two years.

Former detainees at the facility told HRW last year that "interrogators beat them, hung them upside down for hours at a time, administered electric shocks to various body parts, including their genitals, and asphyxiated them repeatedly with plastic bags put over their heads until they passed out."

London-based Amnesty International also said in a February 2011 report that Iraq operates secret jails and routinely tortures prisoners to extract confessions that are used to convict them.