By politics.co.uk staff
Mass protests are taking place across the Republic of Ireland today against the violence of recent days.
Silent protests are due to be held in Belfast, Lisburn, Newry, Downpatrick and Londonderry, while MPs in Westminster are holding a vigil later in the afternoon.
In a separate development, newspaper reports point to cooperation between dissident republican groups over the murders of a policeman and two soldiers.
According to unnamed intelligence sources quoted in the Times, there was a degree of "basic cooperation" in the shootings of Constable Stephen Paul Carroll on Monday and Sappers Mark Quinsey and Patrick Azimkar on Saturday.
The newspaper claims that the Provisional IRA and Real IRA have also been importing modern rifles from outside Northern Ireland.
A 17-year-old boy and a 37-year-old man have been arrested in connection with the murder of Constable Carroll. The 48-year-old Catholic officer was shot in the back of the head as he attended a call in Lismore Manor, Craigavon.
Sappers Quinsey and Azimkar, aged 23 and 21, died when gunmen opened fire as they collected a pizza delivery outside of the Massereene army base in County Antrim. Four others - two soldiers and two Domino's employees - were wounded in the attack, which saw the two victims hit with more than 60 bullets.
The killings have drawn condemnation from both republican and loyalist politicians at Stormont.
Martin McGuinness, former commander of the Provisional IRA and now deputy first minister, said: "These people are traitors to the island of Ireland.
"They have betrayed the political desires, hopes and aspirations of all of the people who live on this island."