Gerry Adams arrest: A windowless cell and a seatless toilet as SF chief checks in to Serious Crime Suite
Last night police chose to question the Sinn Fein leader for another 24 hours, meaning another night in the cramped cell for the veteran republican.
Adams would have spent last night sleeping on a steel-framed, wall-mounted bed with a blue plastic foam mattress. Spring mattresses are not permitted due to the risk of self-harm by suspects.
The sparse rooms in the suite have no windows and a seatless toilet positioned in the corner.
A security camera is mounted on one wall for staff to constantly monitor the behaviour of those inside. Officers can also keep watch through a small peephole in the cell door.
Prior to entering the cell, Adams' personal belongings, including his mobile phone and watch, would have been removed during a search of his clothing.
Suspects have access to refreshments if and when they are required, and eat the same food as station staff, with meals produced in the building's canteen. There is also a microwave nearby, with a selection of basic ready-meals available.
Should an interviewee request a pizza or Chinese takeaway, officers have been known to order them in, with the same applying to cigarettes. While being booked in by the on-duty custody sergeant, suspects are given the opportunity to avail of a phone call if they choose.
Also within the unit, small rooms are designated for consultations between lawyers and suspects.
Adams first contacted police more than a month ago to inform them he was willing to discuss Mrs McConville's disappearance.
Sinn Fein said he did so following high-profile media coverage of claims he was heavily involved in the 1972 murder.
"If the PSNI wish to talk to me on this matter I am available to meet them. I have asked my solicitor to contact them," he said back then.
Police then this week contacted his solicitor, Seamus Connolly, and a time was arranged for his client to meet with investigators.
An interview with RTE took place just prior to his travelling to meet police during which he again strongly denied any involvement in Mrs McConville's murder.
Adams travelled to Antrim PSNI station on Wednesday evening, where he was met by Mr Connolly.
The Serious Crime Suite in Antrim was purpose-built for the detention of those apprehended under the Terrorism Act 2000 and provides accommodation to cater for the extensive questioning of suspects.
Adams was arrested shortly after 8pm under anti-terror legislation.
A statement was released by Sinn Fein on behalf of Adams shortly after his arrest. "While I have concerns about the timing, I am voluntarily meeting with the PSNI this evening," he 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."