Police in Dubai have named five new suspects in connection with the murder of a Hamas officialin January, officials have said.
The five men reportedly carried passports from Britain, Australia and France.
Authorities in New Zealand are also checking whether one of their passports was used by the men.
The Israeli newspaper Ha'aretz reported that one of the five might be an Israeli citizen, Zev Barkan, who has been wanted in New Zealand since 2004for passport fraud.
Lt Gen Dafi Khalfan Tamim, the Dubai police chief, declined to comment on the latest batch of suspects.
Dubai police have already named 27 other people in connection with the killing, and they accuse the Mossad, Israel's spy agency, of carrying out the murder. Interpol has issued arrest warrants for those 27 suspects.
The Israeli government, which maintains a "policy of ambiguity" on Mossad's actions, has not confirmed or denied any role.
Mahmoud al-Mabhouh, a Hamas military commander, was killed in his Dubai hotel room on January 20 by a team of assassins.
Police say he was strangledby the killers, who then fled the country. Many of them were captured on security cameras in the hotel and at Dubai International Airport.
The use of foreign passports in the killing sparked a diplomatic row between Israel and several other countries. The British foreign office expelled an Israeli diplomat last monthover the use of British passports in al-Mabhouh's murder.
But Britain stopped short of linking Mossad to the killing.