Israel has seldom shied from attacking its enemies -- even if it takes years, even on foreign soil, even if it sours relations with allies.

Israeli citizens for the most part have supported such policies and cheered their internationally respected spy agency, the Mossad, which obtained legendary status after hunting down and killing the terrorists responsible for the slaying of Israeli athletes during the 1972 Munich Olympics.

Now the Mossad may be testing the limits of that popularity amid allegations that it used Israeli citizens as pawns in the January assassination of an alleged Hamas arms dealer in a Dubai hotel.

Most Israelis applauded the killing of Mahmoud Mabhouh, who was accused of smuggling arms from Iran and of involvement in the capture and killing of two Israeli soldiers in the 1980s.

But at least seven Israelis awoke this week to find their names on a most-wanted poster released by police in Dubai, in the United Arab Emirates, who are investigating the Hamas slaying.

"I don't understand how something like this could happen," Israeli repairman Paul John Keeley told the Haaretz newspaper. "I'm waiting for someone from the British or Israeli government to contact me and give me some answers."

Keeley and the others said they were victims of identity theft. All of the Israelis whose names were used hold dual citizenship with European nations. Keeley is one of six with British passports. It is believed that forged passports from Ireland and Germany were also used.

The identity-theft victims said they worried that the mix-up could create problems when they travel internationally, or even make them the target of revenge attacks.

Though the Israeli government has refused to confirm or deny its involvement, some inside and outside the country are calling for formal investigations.

"All of this needs to be examined," military analyst Yoav Limor said Wednesday on Israeli radio. "If it is a foreign agency, why did they use Israeli identities? And if it is an Israeli agency, again, why use Israeli identities?"

Israeli Foreign Minister Avigdor Lieberman said the use of passports held by foreign-born Israelis was no proof that the Mabhouh killing was orchestrated by Israel. He defended Israel's refusal to comment as a "policy of ambiguity" designed to keep enemies guessing.

So far, Israeli officials have said that they see no need to investigate the matter or intervene in behalf of the citizens. One parliament member called the matter private and suggested that the victims hire attorneys.

But what first appeared to be a highly professional operation -- in which at least 11 operatives slipped easily in and out of Dubai -- is now threatening to snowball into a diplomatic embarrassment.

Israel's Western allies, particularly Britain, vowed to aggressively investigate how their passports came to be used in the operation.

"The British passport is an important document that has got to be held with care," British Prime Minister Gordon Brown said Wednesday during a radio interview.

Britain has not publicly accused Israel of involvement in the assassination, but it summoned the Israeli ambassador in London to discuss the matter Thursday.

Experts say the assassination has the hallmarks of the Mossad, which has used foreign passports in operations.

Part of the operation was captured on various surveillance cameras in Dubai's hotels and airport. Grainy video shows the alleged assassins, sometimes in wigs or other disguises, arriving at the airport and monitoring the hotel hallway outside Mabhouh's room.

"It has a lot of Israeli fingerprints, but they will never officially confirm it," said Gad Shimron, a former Mossad agent and an author.

Describing the seven Israelis whose names were used as "collateral damage," Shimron said use of real passport names and numbers is increasingly common in covert operations because fake documents are easily spotted by modern technology and international databases.

He said the Mossad may have had no choice but to use identification from Israel's own citizens.

"Mossad, like any intelligence organization, needs good documentation to have a good operation, and they get it wherever they can," Shimron said.

It's too early to tell how the matter will play domestically. Israelis often rally behind the government when foreign criticism mounts.

One newspaper columnist on Wednesday was already calling for the replacement of the Mossad's leader; another questioned whether "Mabhouh was worth all this."

But others defended Israel and even criticized the identity-theft victims for "overreacting," saying they should be willing to sacrifice for their country.

"Anything that is good for the state is good," bus driver Yehuda Cohen said. "I'm a patriot."

Israel's use of foreign passports in covert operations has led to diplomatic clashes. In New Zealand, Mossad agents were arrested in 2004 while attempting to use the identity of a disabled person. Before that, its agents left a bundle of British passports in a German phone booth by accident.

In 1997, Israel's peace agreement with Jordan was strained when the Mossad was accused of using Canadian passports in a failed assassination attempt against Hamas leader Khaled Meshaal.

Each time, Israel apologized and promised not to use the other nation's passports in future operations.

Defense analyst Ron Ben-Yishai said that as long as there was no evidence of the Mossad's involvement, Israel would not suffer any diplomatic backlash.

"All the perpetrators escaped, so you can't link it back to Israel," he said.

One wild card, however, is the arrest of two Palestinians who reportedly met with some members of the hit squad and might be able to identify them.

Palestinian and Dubai officials have refused to release the men's names.

A Hamas spokesman in the Gaza Strip said both men are originally from Gaza and provided information about Mabhouh to the hit squad, but he denied that either was a member of Hamas.

"They were recruited by [Israel] to participate in this cowardly operation," Hamas spokesman Sami abu Zuhri said.