Last Updated Apr 30, 2014 5:00 PM EDT
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.
"A Secret History of the IRA," written by one of Ireland's most respected reporters, Ed Moloney, and published in 2002, claimed that Adams was the mastermind behind a two-decade effort to steer the underground group toward cease-fires and political compromise.
The book also claimed Adams joined the IRA's ruling Army Council in 1977 and sanctioned the secretive group's worst atrocities as he led its legal Sinn Fein party. Adams, Sinn Fein chief since 1983, insisted he was never an IRA member.
A woman named Dolours Price admitted to CBS News a year and a half ago that she drove the car the night McConville was abducted and killed.
She said Adams had ordered the killing.
Price, who has since died, also accused Adams of ordering a bombing that she carried out in London.
"Who sent me to London to blow it up?" she asked. "Gerry Adams."
In a statement released via Sinn Fein following his arrest, Adams said:
"As a republican leader I have never shirked my responsibility to build the peace. This includes dealing with the difficult issue of victims and their families. Insofar as it is possible I have worked to bring closure to victims and their families who have contacted me. Even though they may not agree, this includes the family of Jean McConville.
"I believe that the killing of Jean McConville and the secret burial of her body was wrong and a grievous injustice to her and her family.
"Well publicised, malicious allegations have been made against me. I reject these.
"While I have never disassociated myself from the IRA and I never will, I am innocent of any part in the abduction, killing or burial of Mrs McConville."