A devastating report into the final months of Sri Lanka's brutal civil war claims government forces carried out a politically-motivated massacre of surrendering Tamil Tiger fighters.
The investigation by a leading Sri Lankan human rights group accuses elements of the Sri Lankan army of touching "the most depraved depths of humanity".
But it also accuses the Liberation Tigers of Tamil Eelam [LTTE] of torture, murder, and the forced conscription of children, and says the rebel group was probably responsible for most of the thousands of civilian casualties in the final days of the war.
The report was issued last night by the University Teachers for Human Rights (Jaffna) group, which has spent 21 years exposing abuses by both sides in the civil war.
Its investigators uncovered evidence that LTTE fighters gunned down civilians who they believed were trying to escape and that government troops threw grenades into bunkers where they knew civilians were sheltering and used a vehicle to run over injured civilians. There are also allegations that wounded civilians may have been bulldozed into mass graves along with the dead.
The most controversial claim, however, is that the government authorised a massacre of LTTE cadres after persuading them to surrender.
Citing sources within the Sri Lankan armed forces, the report points to a "politically ordered massacre of people who wanted to surrender or surrendered".
It adds: "The army had for the most part conducted itself in a disciplined manner in trying to protect civilians. But once the command gives a signal for barbarity to be let loose, the men touch the most depraved depths of humanity."
The report comes as Amnesty International called on the Sri Lankan government to overhaul its justice system if it was to secure lasting peace.
"If communities that have been torn apart by decades of violence and impunity are to be reconciled, the Sri Lankan government should initiate internal reforms and seek international assistance to prevent ongoing violations and ensure real accountability for past abuses," said Sam Zarifi, Amnesty International's Asia-Pacific director.
In a separate report released today, Amnesty called for an international commission to investigate allegations of abuse and torture, saying that past government probes had had no impact.
Amnesty's findings were given extra weight by the Jaffna report, which found that cornered LTTE fighters were killed after being persuaded by government forces to destroy most of their weapons and to give themselves up.
"Claims of a massacre have been emanating from the security forces … these were messages from very senior officers, middle-ranking officers and personnel. They were posted in various areas. Some heard it from friends on the scene and others from the armed forces grapevine. The common substance was the same: all LTTE members who were left there were massacred, including the women and children."
The researchers also questioned the use of earth-moving equipment to dispose of the bodies inside the no-fire zone.
"Given also the fact that earth-moving equipment was used to clear the area before the president's victory announcement the following day, we need to ask if adequate care was taken to separate the dead from the injured and the dying. On the testimony of civilians there were several injured persons asking for help."
The report was equally damning about the LTTE and its supporters overseas.
The authors said the rebel group had "tortured, robbed, murdered the people, suffocated alternative voices and conscripted their children in the name of liberation".
It continued: "Even as the LTTE leaders were discussing surrender terms, they were sending out very young suicide cadres to slow down the army advance."
It said sections of the Tamil diaspora "blindly supported the LTTE's terror at home and its political articulation of people as weapons of mass suicide".
It added: "Some cadres were going to bunkers where civilians were sheltering, asking, 'So you want to run away to the army, do you?', and then opening fire at them."
The report suggested that between 1,000 and 4,000 people were killed on the final night of fighting, with the LTTE responsible for the large majority of civilian deaths.