Sinn Féin leader Gerry Adams has been released from custody over a 1972 murder and a file will be sent to the Public Prosecution Service, police have confirmed. Mr Adams had been questioned at Antrim PSNI Station since Wednesday, after he was arrested in connection with the murder of Jean McConville. The 37-year-old widow and mother of 10 was abducted from her home in west Belfast, shot and secretly buried by the IRA. Her body was found on a beach in County Louth in 2003. Mr Adams has always denied involvement in the killing. Police had until 20:00 BST on Sunday to charge or release Mr Adams. Mr Adams, a former MP for West Belfast and now an elected representative for County Louth in the Irish parliament, presented himself for interview by prior arrangement with detectives on Wednesday night. He was then arrested under the terrorism act. He was questioned for two days before the police successfully applied to a judge in Belfast on Friday for a 48-hour extension to his detention period. Sinn Féin had condemned the arrest, claiming it was political and hinting that they might reconsider their support for the police. However, unionists said no-one should be above the law and Democratic Unionist leader and Northern Ireland First Minister Peter Robinson accused Sinn Féin of trying to "blackmail" the police. The decision to release Mr Adams would mean that prosecution lawyers will decide if charges will be brought. The file sent by the police to the Public Prosecution Service (PPS) will detail the evidence gathered. It will be up to PPS lawyers to decide if there is enough evidence to bring any charges and what those charges would be. The test for prosecution is met if there is sufficient evidence that can be admitted in court to provide a reasonable prospect of conviction. Lawyers must also decide if the prosecution is required in the public interest.