London, England (CNN) -- European officials pressed Israel for answers Thursday over the use of fraudulent passports by suspects in the killing of a top Hamas official, following media speculation that Israeli agents were involved.
It came as Interpol made public the photos and fraudulent names of 11 people it said were involved in the murder in Dubai last month. The "red notices" are not international arrest warrants, but are a way of alerting police forces around the world that the suspects are wanted by authorities in the United Arab Emirates.
British and Irish officials met with their respective Israeli ambassadors, and France demanded that Israel explain the use of one French passport in the plot, the French Foreign Ministry said.
British Foreign Secretary David Miliband said Britain was determined to get to the bottom of the passport issue. The Israeli ambassador to London, Ron Prosor, met at the British Foreign Office with Peter Ricketts, the head of Britain's diplomatic service.
"I was unable to add additional information to Sir Peter Ricketts' request," Prosor told reporters.
Miliband said Ricketts "made clear how seriously we take any suggestion of fraudulent use of British passports," and explained Britain's concern for the British nationals, currently living in Israel, whose passports were apparently used in the plot.
Ricketts told the ambassador "that we wanted to give Israel every opportunity to share with us what it knows about this incident, and we hope and expect that they will cooperate fully with the investigation that has been launched," Miliband said.
Authorities in Dubai released the photos and fraudulent names of 11 members of an alleged hit-squad that killed Mahmoud al-Mabhouh, a founding member of Hamas' military wing, in his Dubai hotel room last month.
The suspects had European passports -- one from France, three from Ireland, six from Britain, and one from Germany, according to police.
A senior United Arab Emirates official involved in the investigation, however, told CNN there are seven more suspects involved -- including two Palestinians -- for a total of 18. The two were arrested in Jordan, according to the official.
The passports used are not fake or forged, but are authentic passports meant for other people, the official said.
Police are working to identify the five other suspects, the official said.
British Prime Minister Gordon Brown has already ordered an investigation, after British officials said they believe the passports used were fraudulent. France has also said a passport used from that country is fraudulent.
"We have got to know what happened to British passports," Brown said in a statement Thursday. "It is as simple as that. It is an investigation that has got to take place before any conclusions are drawn."
In Israel, as many as seven people whose names were on the travel documents said they have no knowledge of al-Mabhouh's death.
At the same time that Prosor met with Ricketts, Israel's ambassador to Ireland, Zion Evrony, met with David Cooney, Ireland's foreign affairs secretary general.
"The main issue raised was the fraudulent use of Irish passports by persons believed to have committed a murder in Dubai," an Irish Foreign Ministry statement said. "Details were provided to the ambassador of the fake passports and the Israeli authorities were requested to provide whatever information and assistance they could in this matter."
An Irish Foreign Ministry spokesman, who could not be named in line with policy, said they are demanding answers of Israel because of "media speculation" about Israeli involvement.
The Dubai police chief said Thursday that it is "99-percent" certain that Mossad, the secretive Israeli intelligence unit, is behind al-Mabhouh's killing.
"Our investigations reveal that Mossad is involved in the murder of al-Mabhouh. It is 99 percent, if not 100 percent that Mossad is standing behind the murder," Lt. Gen. Dahi Khalfan Tamim told The National newspaper, an English-language daily owned by the ruling family of Abu Dhabi.
Dubai police have evidence that shows a clear link behind the suspects and people closely connected to Israel, Tamim told the paper, but he did not say what the evidence is.
Hamas has called al-Mabhouh's death an assassination. His family members told CNN they believed Mossad was involved.
Al-Mabhouh was behind the kidnapping and killing of two Israeli soldiers in 1989, according to Hamas.
"The decision for revenge has been made and the Zionists must wait for that moment and see," said Abu Ubaida, a spokesman for Al-Qassam Brigades, the armed wing of Hamas.
Israel has a policy of neither confirming nor denying involvement in security matters, and government officials declined to comment on the "assassination" statement.
"The Israeli policy has always been to be vague regarding security activities, and that is the right policy," Foreign Minister Avigdor Lieberman told Israel Army Radio on Wednesday.