Irish republican leader Gerry Adams on Sunday criticised the Northern Ireland police's handling of his arrest over a notorious IRA murder, saying it sent a wrong signal for the peace process to which he remains "totally committed".
"Those that authorised this (arrest) didn't make the right strategic decision," Adams said at a press conference in Belfast's Balmoral Hotel. "This is entirely a wrong signal".
Adams, a key figure in the peace process, was arrested on Wednesday in connection with the death of Jean McConville, a mother-of-ten abducted from her home in 1972.
The Police Service of Northern Ireland (PSNI) freed Adams at around 5:30 pm (1630 GMT) after four days of questioning.
The republican leader could still face charges when a file is sent to prosecutors, and the Times on Monday reported police had recommended prosecution.
The Sinn Fein president claimed that much of the evidence presented to him during 33 taped interviews came from newspaper articles, books and photos, and that the allegations against him were part of a "sustained, malicious, untruthful and sinister campaign".
He suggested that the timing of his four-day detention was politically motivated with European elections due to be held later this month.
"I make the case that those who authorised my arrest and detention could have done it differently, " he said, flanked by Deputy First Minister Martin McGuinness, the top Sinn Fein member in the power-sharing government.
"They did not have to do this in the middle of an election campaign."
Adams explained that he voluntarily contacted police two months ago after newspaper reports linked him to the murder.
He also repeated his commitment to the US-backed Good Friday accords in 1998 that largely ended three decades of sectarian violence, and pledged his support for the PSNI despite earlier suggestions from Sinn Fein that the arrest could force a review of its policy.
"There can be no going back," he insisted. "We are totally and absolutely committed to the peace process.
"I want to make it clear that I support the PSNI, I will continue to work with others to build a genuinely civic police service.
"The old guard which is against change, whether in the PSNI leadership, within elements of unionism or the far fringes of self-proclaimed but pseudo republicanism, they can't win," he added.
"The dark side of the British system cannot be allowed to deny anyone... from our entitlement to a rights-based, citizen-centred society."
Sinn Fein's support for a reformed police force in Northern Ireland, after long accusing the police of collusion and anti-Catholic bias, was a key part of the Good Friday agreements.
The PPS must now decide whether there is enough evidence to charge Adams, or whether prosecution would be in the public interest.
Barra McGrory, Northern Ireland's director of public prosecutions, has passed on the case as he used to act as Adams's solicitor.
He strongly denies any involvement in the murder, just as he denies ever having been a member of the IRA, and offered sympathy "to the McConville family, and to all those who have suffered, especially at the hands of republicans".
The renewed attention on the case was sparked by interviews given by former IRA members to Boston College.
"I reject all the allegations, and rejected all the allegations made against me in these tapes," he said.
Adams left in a police convoy via the back door of Antrim police station, where he had been held, in order to avoid a vocal group of Union Jack flag waving loyalist demonstrators, who want the province to remain British.
Tensions in Northern Ireland have risen since Wednesday's arrest, with around 400 republicans attending a march on Saturday in west Belfast.
Sinn Fein shares power in the Northern Ireland assembly with the Protestant conservative Democratic Unionist Party of First Minister Peter Robinson.
McConville's children watched as she was dragged screaming from their Belfast home in 1972 after the IRA accused her of being an informer. Her remains were found buried on a beach in 2003 and tests found she had been shot in the back of the head.
Around 3,500 people died in three decades of violence in Northern Ireland known as "The Troubles."
The province has been largely peaceful but sporadic attacks continue, blamed on dissident republicans opposed to the peace process, and communal unrest erupts from time to time.