Sinn Féin has confirmed that the PSNI has warned of a second threat to the life of party leader Gerry Adams.
A party spokesman confirmed the West Belfast MP was alerted to the threat by the police. "Sinn Féin takes all of the recent threats seriously," he said.
The latest threat comes almost two and a half weeks after it was reported that hard-line republicans had threatened Mr Adams, Martin McGuinness and Gerry Kelly.
Sinn Féin's confirmation of the threat came just hours after a letter to a Belfast newspaper from the loyalist Michael Stone said he had planned to kill Mr Adams and Mr McGuinness in the Northern Ireland Assembly last Friday.
Mr Stone was arrested after he tried to launch a bomb attack at Stormont. A Sinn Féin spokesman said they were aware of the threat from a number of quarters to their leadership.
"We are very mindful that there are elements within the British system, within unionism, and some disaffected republicans who are opposed to the Sinn Féin strategy and are prepared to take extreme action to pursue their narrow agenda," he said.
"Sinn Féin will obviously take whatever precautions we can to minimise the danger but we will not be deflected from continuing to do the work we were elected to do."
Sinn Féin is understood to be concerned that disaffected Provisional IRA members or members of existing dissident republican groups such as the Real IRA and the Continuity IRA are behind the security threats.