Read more: Time to stand up to Northern Ireland killers ---They disgrace the good name of the Irish worldwide

Read more: Northern Irish policeman murdered in dissident bomb attack in Omagh

Detectives in Scotland have arrested a man in connection to the murder of Constable Ronan Kerr in Omagh, County Tyrone on Saturday. The arrest came after a significant arms find in the Coalisand area in Tyrone.

The Police Service of Northern Ireland (PSNI) found four rifles, detonators, component parts for rockets and explosives believed to be Semtex. The weapons were found in a garage unit at Mountjoy Road, Coalisand.

The man arrested was initially questioned with relation to the weapons find. He is now being questioned over the murder of the 25-year-old rookie Catholic police officer. He was arrested by armed police in a small town outside Renton, in Dunbartonshire, west of Glasgow. The operation was carried out between Strathclyde and the PSNI. Soon he will be transferred to Northern Ireland.

Speaking at Kerr's funeral Cardinal Sean Brady appealed to republican dissident to end the violence. He called Kerr's murder "an evil deed, an offence against God".

He spoke directly to the killer saying "We do not want this. In God's name stop – and stop now…Choose life, I say. Choose goodness, choose peace."

Kerr was murdered when a booby-trap bomb left under his car exploded outside his home in Omagh.

Although no group has claimed responsibility for the killings republicans are being blamed. Graffiti in the Bogside area of Derry warned there would be more killings if Catholic continued to join the PSNI.

Read more: Time to stand up to Northern Ireland killers ---They disgrace the good name of the Irish worldwide

Read more: Northern Irish policeman murdered in dissident bomb attack in Omagh