Hundreds of new cases accusing British soldiers of abusing – in many cases torturing – Iraqi men, women and children, aged from 13 to 101, are to be considered by the International Criminal Court (ICC).

Britain is already under scrutiny for alleged war crimes committed by its forces in Iraq. The ICC is currently examining a dossier of claims presented by lawyers and human rights campaigners earlier this year that could lead to a full investigation.

The fresh details come on the eve of the publication of an official report into allegations that British soldiers mistreated and unlawfully killed Iraqis in 2004. The report, to be released on Wednesday, is expected to criticise the abuse of Iraqi prisoners captured after a battle. A number of "warning letters" have been sent to individuals believed to face criticism in the report.

The revelations will fuel the row surrounding official British knowledge of the use of torture to obtain intelligence from suspected insurgents and terrorists. Pressure is mounting on David Cameron to order a full judicial inquiry into what Britain knew about torture by America's CIA and other allies fighting al-Qaeda-inspired terror.

Yesterday, the SNP called for a full judicial inquiry to examine the UK government's role in extraordinary rendition and for the findings of the Chilcot inquiry into the Iraq war to be made public. SNP Defence spokesperson Angus Robertson MP said: "Despite the appalling findings of the US Senate report about inhumane treatment of detainees, we have seen no urgency from the UK government to get to the truth on this matter. A full judicial inquiry must now be established to determine what the UK government knew about the flights that passed through airports in the UK, including Scotland, and whether ministers were aware of the human rights abuses that we now know may have occurred in this country."

The latest cases being sent this week to the ICC in The Hague as well as to the Ministry of Defence's Service Prosecuting Authority include harrowing accounts covering a five-year period, from 2003 to 2008. The allegations, in court documents obtained by this newspaper, highlight a systematic approach of beating and hooding before brutal interrogations; these actions took place after ministers had claimed that such methods were no longer being used by British forces in Iraq.

Some of the victims insist their only crime was being in the wrong place at the wrong time, or being a victim of mistaken identity. Some were kept for just a few hours, others for many months.

Iraqi detainees stand behind a fence at the Camp Bucca detention centre, located near the Kuwait-Iraq border (Getty)

Claims of electrocution, sleep deprivation and people being forced to stay in painful stress positions for hours are included throughout the documents – in an approach strikingly similar to the "enhanced interrogation" techniques of the CIA. The cases also reveal that hooding was still widely used years after Geoff Hoon, then defence secretary, told MPs in 2005 that it had not been used in Iraq since May 2004. In fact, there were more than 70 cases of hooding between June 2004 and September 2008, according to the documents.

Dozens of cases detail mock executions, while many others describe how dogs were used to attack or threaten detainees. There are also allegations of sexual assault or rape by British soldiers.

Many victims have been left scarred for life. One government worker, 34, reported to have been "repeatedly beaten" and "electrocuted", suffered "severe psychological injuries as a result of his treatment.... He set himself alight and killed himself approximately one year after his release".

One document says the wife and daughters of a fireman aged 60 "were punched, slapped... and beaten with rifles" during a raid on his home in December 2003 in which he was beaten unconscious.

And a 20-year-old man, arrested in April 2003, "was repeatedly punched in the face by a soldier who sang as he hit him. He noted the soldier enjoyed hitting him." He then spent time in a "guest house" where detainees "were made to kneel and put their head on the floor ... he was repeatedly hit and threatened at gunpoint by one soldier who would check on him every three or four hours and ensure that detainees had not moved".

In another case, a 29-year-old Iraqi police officer died after his home was raided in June 2008. The document says that his family saw how soldiers "forced his head into a bucket of cold water a number of times. He stopped breathing and died. His wife and children witnessed the soldiers killing him". It adds: "The head of the police department requested an explanation.... British forces admitted they mistakenly killed the deceased," the statement says.

Civilians claim they were repeatedly electrocuted. A 20-year-old fisherman, arrested in June 2004, tells how "his back was electrocuted a number of times; the pain ran through to his genitals which began to bleed. He lost consciousness and woke up inside his cell." Others were abused in their homes. After they broke into his home in April 2006, soldiers took a 31-year-old man to the bathroom where he was "beaten, urinated on, interrogated and waterboarded more than five times".

Another of the claims concerns a man of 28 who was found outside Camp Bucca a month after being arrested by British forces in April 2003. "He had head injuries, a broken leg, his arm was paralysed and his speech became impaired so that he now speaks much like a young child."

Phil Shiner, a solicitor with the law firm PIL (Public Interest Lawyers), which is handling the claims, said: "These cases involving the most serious human rights violations imaginable pose immensely difficult questions. The UK mindset in Iraq appears to be one of savage brutality and a sadistic inhumanity, irrespective of whether it was women, children or old men being tortured, abused or callously subjected to lethal force. The systemic issues must now be dealt with in public."

A Ministry of Defence spokesperson said: "We are concerned that hundreds of claims are coming forward many years after the alleged events in Iraq, which must raise questions about their credibility, particularly since no supporting evidence has been provided in many cases."

Mr Shiner said: "They knew about all these cases all along and always had a legal duty to investigate, irrespective of any complaints."

Additional research by Harry Davies

In quotes: Extraordinary rendition

18|03|04 "Most importantly, I congratulate you [Gaddafi] on the safe arrival of Abu Abd Allah Sadiq [Belhadj]. This was the least we could do for you and for Libya to demonstrate the remarkable relationship we have built over the years. I am so glad. I was grateful to you for helping the officer we sent out last week. Abu Abd Allah's information on the situation in this country is of urgent importance to us."

Mark Allen, former MI6 director of counter-terrorism

13|12|05 "Unless we all start to believe in conspiracy theories and that the officials are lying, that I am lying, that behind this there is some kind of secret state which is in league with some dark forces in the United States, and let me say, we believe that Secretary [Condoleezza] Rice is lying, there simply is no truth that the United Kingdom has been involved in rendition, full stop."

Jack Straw on the use of Diego Garcia for rendition

11|10|07 "The US authorities have repeatedly given us assurances that no detainees, prisoners of war or any other persons in this category are being held on Diego Garcia, or have at any time passed in transit through Diego Garcia or its territorial waters or airspace."

Meg Munn, former foreign minister

21|02|08 "I am very sorry indeed to have to report to the House the need to correct... statements on the subject."

David Miliband, former Foreign Secretary, on Diego Garcia

27|03|09 "Only a judge-led inquiry can enable us to draw a line under all of this, and give the public confidence that we will finally get to the truth on rendition."

Andrew Tyrie, chairman of the All Party Committee on Rendition

29|08|10 "The facts are that bad things were done by the Americans after 2002 and they didn't tell anyone else. Slowly the pieces of the jigsaw were put together and when they were put together the British government acted. Should we have been faster to put those pieces of the jigsaw together? Yes."

David Miliband, former Foreign Secretary

09|12|14 "Look, I don't want to mislead you, and I would be hypocritical if I didn't tell you that I don't have a problem with killing terrorists."

James Mitchell, co-architect of CIA's enhanced interrogation techniques

10|12|14 "The men and women of the CIA did exactly what we wanted. We said we've got to go use enhanced techniques… and we're going to find out. We've got Khalid Sheikh Mohammed, who's the mastermind of 9/11, and he is in our possession, we know he's the architect. And what are we supposed to do? Kiss him on both cheeks and say please tell us what you know? Of course not."

Dick Cheney, former US Vice-President

11|12|14 "Our reviews indicate that the detention and interrogation programme produced useful intelligence that helped the United States thwart attack plans, capture terrorists and save lives."

John Brennan, director of the CIA

11|12|14 "I thought Nick Clegg's reaction was very disappointing. His reaction should not be of 'openness' to a judicial enquiry. He should be actively pushing for a judicial enquiry. The Government came to power four years ago. He's had ample opportunity to uncover, as Deputy Prime Minister, what was going on. We've now pushed it off to a rather pitiful parliamentary committee with no teeth... and again it just goes into the long grass."