The families of 11 people shot dead by paratroopers in West Belfast are to present the British secretary of state for the North, Owen Patterson, and Stormont justice minister, David Ford, with a new dossier of evidence on the killings.

Campaigners for the Ballymurphy massacre victims are demanding an independent international inquiry, a statement from the British government declaring the innocence of the dead, and a public apology. Their call for an independent inquiry is backed by the Catholic Church, Sinn Féin, and the SDLP.

Next week marks the 39th anniversary of the massacre. Eleven unarmed civilians, including a 45-year-old mother of eight and a Catholic priest, were killed as paratroopers went on the rampage.

Relatives told the Sunday Tribune that the Irish government had donated £20,000 towards a report into the killings which took place over three days following the introduction of internment on 9 August 1971.

The money has funded a report by Kevin Winters' solicitors. Briege Voyle, whose mother Joan Connolly was killed, said more than 100 eyewitnesses had been interviewed.

The dossier will include information from autopsies and analysis of forensic and ballistics reports. Documents have also been obtained under the Freedom of Information act.

"The report will be the most definitive account yet of those three awful days in Ballymurphy," Voyle said. "It will establish the sequence of events as they unfolded as accurately as possible, though it will contain more questions than answers."

The dossier will be completed within six weeks and sent to Owen Patterson and David Ford. The families hope to meet both politicians. The Ballymurphy massacre was carried out by 1 Para, the same regiment which six months later murdered 13 civilians on Bloody Sunday.

Voyle said the Saville inquiry should have examined the Ballymurphy killings. "We're delighted the Bloody Sunday families have at last got some form of justice with the Saville report," she said. "But we're also worried that it means we face an even more uphill battle. It's highly unlikely that having admitted to one atrocity, the British Army will quickly admit to another one."

The Ballymurphy massacre proved Bloody Sunday wasn't an aberration, she said: "It shows the paras didn't go on a one-off bender in Derry with their superiors losing control. They were a killing machine, sent to give Ballymurphy a bloody nose, then sent six months later to do the same in the Bogside."

The soldiers' shooting spree in Ballymurphy left 54 children without parents. The British Ministry of Defence claimed those killed were armed. "Not only did they physically murder our parents," said Alice Harper whose father Danny Teggart was shot dead. "They also murdered their good names."

The families said the British army harassed them for years afterwards. Briege Voyle said their home was regularly raided and once the British army mockingly played The Last Post outside the house.

But it was the lies about the victims which most angered relatives. "One soldier said my mother had opened fire on him with a Browning machine gun. She was killed going to help a young lad who had been shot. My mother wouldn't have known what a Browning was. Her only vice was going to bingo," Voyle said.