It is understood that Seán Ó Muireagáin, the Irish language activist from West Belfast, detained in Israel since last Saturday, will most likely be released from custody tomorrow.

An Israeli government spokesperson is reported to have admitted that a mistake had been made regarding Mr Ó Muireagáin’s arrest, but that he had to be detained for cross-checking purposes.

Mr Ó Muireagáin was arrested in Ramallah last Saturday on foot of information received by the Israeli authorities from British intelligence sources.

The government spokesperson said that he was very forthcoming and co-operative with them during his detention.

It is not yet clear whether Mr Ó Muireagáin will be deported on his release.

He is a member of the Ireland Palestine Support group and an occasional contributor to TG4, Raidió na Gaeltachta and the daily newspaper, LÁ.

Mr Ó Muireagáin is also involved in arranging educational exchange programmes for children from the West Bank.

The SDLP's Sean Farren earlier called on the Israeli authorities to immediately release the him.

He said that once again, the British security services appeared to have got it wrong.