CORRECTS SPELLING FROM MCCONCILLE TO MCCONVILLE FILE - In this Thursday Jan. 12, 2012 file photo, Helen McKendry holds a family photo with her mother Jean McConville, at home in Killyleagh, Northern Ireland. Police in Northern Ireland arrested Sinn Fein party leader Gerry Adams on Wednesday, April 30, 2014, over his alleged involvement in the Irish Republican Army's 1972 abduction, killing and secret burial of McConville. (AP Photo/Peter Morrison, file) (The Associated Press)
Michael McConville, the son of Jean McConville who was murdered by the IRA, speaks to the media at the Wave Trauma centre in Belfast, Thursday, May, 1, 2014. Sinn Fein President Gerry Adams is still being questioned by police at Antrim police station after being arrested late Wednesday in connection with the murder of Jean McConville. (AP Photo) (The Associated Press)
FILE - In this Tuesday, Dec. 31, 2013 file photo, Sinn Fein President Gerry Adams speaks to the media at Stormont Hotel, Belfast, Northern Ireland. Northern Ireland police say they have arrested Sinn Fein leader Gerry Adams on suspicion of involvement in the Irish Republican Army's 1972 abduction, killing and secret burial of a Belfast widow. Adams confirmed his own arrest Wednesday in a prepared statement and described it as a voluntary, prearranged interview. Police had been expected to question the 65-year-old Adams about the 1972 killing of Jean McConville, whom the IRA executed as an alleged spy. The IRA did not admit the killing until 1998. Adams was implicated in the killing by two IRA veterans who gave taped interviews to researchers for a Boston College research project. The Northern Ireland police took legal steps to acquire the interviews, parts of which have already been published after one IRA interviewee died. (AP Photo/Peter Morrison, file) (The Associated Press)
The heavily fortified Police station in Antrim, Northern Ireland, Thursday, May, 1 2014. Sinn Fein leader Gerry Adams has been arrested and is being questioned at Antrim police station about the 1972 murder of Jean McConville. (AP Photo/Peter Morrison) (The Associated Press)
BELFAST, Northern Ireland – Sinn Fein leader Gerry Adams remains in police custody as detectives question him over his alleged role in the Irish Republican Army killing of a Belfast mother of 10 in 1972.
Under British anti-terrorist law, Adams must be charged or released by Friday night, unless a judge approves an extension.
Senior politicians in Adams' Irish nationalist party have accused those behind Wednesday's arrest of the 65-year-old of pursuing an anti-Sinn Fein agenda.
Adams denies any role in the outlawed IRA. Former members who spoke on tape to a Boston College-commissioned research project have linked him to the abduction, slaying and secret burial of Jean McConville, a 38-year-old widow whom the IRA branded a British spy. An official 2006 investigation dismissed this claim.