Gerry Adams spends a second night in police custody after his arrest by detectives investigating the notorious IRA murder of a Belfast mother-of-10.
Officers resumed questioning the 65-year-old Sinn Fein leader on Friday about the killing of Jean McConville in 1972.
Mr Adams has always vehemently denied allegations levelled by former republican colleagues that he ordered the murder of Mrs McConville, who was wrongly suspected of being an informer to the British army.
The former West Belfast MP and current representative for Co Louth in the Irish Dail can initially be held for up to 48 hours without charge – a time period that ends at around 8pm on Friday.
Read more: who was Jean McConville, one of N.Ireland's 'disappeared'?
But detectives have the option to apply to a judge today for his detention to be extended for further questioning.
Mrs McConville was dragged screaming from her children in the Divis flats in west Belfast by a gang of up to 12 men and women.
She was interrogated, shot in the back of the head and then secretly buried – so becoming one of the “disappeared” victims of the Troubles. Her body was not found until 2003 on a beach in Co Louth, 50 miles from her home.
Mr Adams’s long-standing party colleague and friend, Stormont Deputy First Minister Martin McGuinness, claimed the arrest was aimed at inflicting political damage on Sinn Fein in the month of an election and said it was an example of the “dark side” of policing trying to flex its muscles.
“I view his arrest as a deliberate attempt to influence the outcome of the elections that are due to take place in three weeks’ time, north and south on this island,” he said.
“That raises very serious questions around why that is the case and what is the agenda.”
But Prime Minister David Cameron rejected any suggestion the arrest was politically motivated. “There has been absolutely no political interference in this issue,” he said.
He added: “We have an independent judicial system, both here in England and also we do have one in Northern Ireland.
Read more: 'Dark side' of police behind Adams arrest - Martin McGuiness
“We have independent policing authorities, independent prosecuting authorities. Those are vital parts of the free country and the free society we enjoy today.”
Mr Adams has always denied IRA membership or any role in Mrs McConville’s death and said in March he would be available to meet detectives if they wished to speak with him.
He presented himself at the police station by prior arrangement and issued a statement through his party minutes after the PSNI announced an arrest had been made.
“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,” he said on Wednesday.
While I have never disassociated myself from the IRA, I am innocent of any part in the abduction, killing or burial of Mrs McConvill. Gerry Adams
“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.”
An investigation carried out by the Northern Ireland police ombudsman has rejected the claims that Mrs McConville was an informer.
Clearly embarrassed by the killing, the IRA did not officially admit responsibility for the murder until 1999 when information was passed to police in the Irish Republic.
It was not until August 2003 that her remains were found on Shelling Hill beach, Co Louth.