Irish Foreign Minister Michael Martin, who is visiting the Hamas-controlled Gaza Strip, said Thursday his country was "very angry" for using fake Irish passports in the killing of a Hamas commander in Dubai last month.

"We are very angry at the use of information that was stolen from valid Irish passports to make faked, forged passports," Martin told reporters in Gaza. "These people are not Irish citizens" and those who forged the passports "also put at risk the security of our citizens."

On Wednesday, Dubai police said it has identified another 15 suspects in killing Mahmoud al-Mabhouh, a Gaza-born Hamas commander, at his hotel room on Jan. 19. The 26 suspects include six holders of Irish passports.

Hamas accused Israel's foreign intelligence unit, Mossad, of killing al-Mabhouh for his role in capturing and murdering two Israeli soldiers in 1989.

Martin crossed through Rafah crossing point between Gaza and Egypt in a visit arranged with the United Nations Relief and Works Agency (UNRWA) which provides aid to more than half of the coastal Strip's 1.5 million people.

In his one-day visit, Martin did not meet any official from Islamic Hamas movement.