Irish diplomats were today investigating reports that two more Irish passports were linked to a team of assassins who murdered a senior Hamas official in Dubai.

Authorities in the United Arab Emirates (UAE) are believed to have identified a further two passport numbers allegedly used by suspects in the assassination of Mahmoud al Mabhouh last month.

It has also emerged that the address of a Dublin property owned by James Reynolds, the brother of former Taoiseach Albert Reynolds and father of music promoter John Reynolds, was given to a hotel by one of five suspects using the fake documents.

A man travelling under the name of Kevin Daveron said he lived at 6 Elgin Road in leafy Dublin 4.

Officials from the Department of Foreign Affairs are liaising with staff at the Irish Embassy in Abu Dhabi to confirm the accuracy of reports.

"We are continuing to work closely with authorities in UAE and our EU partners to establish the facts about this case," a spokesman said.

Hamas commander al-Mabhouh was killed by suspected agents from Israel.

Five forged Irish passports initially linked to the 18 strong hit squad were found in the Emirate with authentic numbers but names which did not match.

However, Israeli Foreign Minister Avigdor Lieberman and Israel's Ambassador to Ireland, Dr Zion Evrony, have both told the Irish Government they have no information about the killing or the forged documents.

Clones of passports belonging to six British Israelis were also among those used by the team of assassins.

The documents were among European identity papers revealed by police as blame for the assassination centred on agents from Israel's Mossad secret service.

Fine Gael called on Foreign Affairs Minister Micheal Martin to brief the Dail on the details of the case urgently.

Billy Timmins, the party's foreign affairs spokesman, said: "The Minister for Foreign Affairs must start getting explanations as to how suspects in an assassination overseas were able to use valid Irish passport numbers on fake passports and provide a bona fide Dublin address when checking out of a hotel."

He added: "The Irish passport has great standing internationally and the minister must do all he can to ensure its status is not debased.

"The illegal use of an address is also a worrying development in this matter."

Elsewhere, Labour's Proinsias De Rossa called on the Irish Government to press the EU to put on hold current proposals to upgrade relations with Israel.

"The stealing of Irish citizens' identities and the abuse of Irish passports by another state is a gross infringement of Irish sovereignty," said the Member of the European Parliament.

"It is not the normal practice for friendly states to abuse each other's sovereignty in this way.

"One can only assume that Israel either has no regard for international law or holds Ireland and the other EU states affected in contempt."

Dr David Lanby, chairman of the Ireland-Palestine Solidarity Campaign, said: "The Israeli denial of involvement in the Dubai assassination has been wholly unconvincing and more a case of 'if you can't prove it, then we won't admit it'.

"Israel is treating the international community with contempt."

PA Media