The PSNI has been granted a further 48 hours by a judge to question Sinn Fein leader Gerry Adams.
He was detained on Wednesday night in connection with the 1972 abduction and murder of Belfast mother-of-ten Jean McConville.
He denies any involvement.
He will remain in custody at the Serious Crimes suite at Antrim police station until tomorrow at the earliest.
He was arrested on Wednesday evening, and the PSNI sought an extension as the original 48 hours limit for detention without charge expired at 8pm tonight.
An application for a further detention period was made this afternoon.
Earlier, the North's Deputy First Minister, Martin McGuinness, said the arrest of Mr Adams was politically motivated.
“Today’s decision by the PSNI to seek an extension confirms me in my view,” he said.
Mr McGuinness said Sinn Féin would "reflect" and "review" its support for policing in the region if Mr Adams is charged.
But he urged republicans to remain calm if and until that happened.