Jerusalem (CNN) -- The killers of Hamas leader Mahmoud al-Mabhouh first injected him with a muscle relaxant and then suffocated him, Dubai police said Sunday.
Toxicology tests on the Hamas leader found significant amounts of succinylcholine, a drug that is used to relax muscles during surgery or as an anesthetic.
"The assassins used this method so that it would seem that his death was natural," Maj. Gen. Al Mazeina said.
But signs indicated that al-Mabhouh resisted his attacker as they suffocated him, police said.
The latest determination are in line with what police disclosed earlier and told al-Mabhouh's relatives.
Family members were told that police had found blood on the pillow. Authorities have also said the killers left some of al-Mabhouh's medicine next to his bed in an apparent effort to suggest his death was not suspicious.
Al-Mabhouh, a founding member of Hamas' military wing, was found dead in his hotel room in Dubai, United Arab Emirates, on January 20.
Police believe he was killed the night before and suspect the Mossad, the secretive Israeli foreign intelligence unit, was behind his slaying.
Israeli Foreign Minister Avigdor Lieberman has said only "media reports" link Israel to al-Mabhouh's death.
A total of 26 suspects have been identified by Dubai police. The suspects are believed to have acquired faulty passports to arrive in Dubai for the killing and then fled to other far-flung locations, police said.
The 26 named suspects do not include two Palestinians previously arrested in Jordan and returned to the UAE.
Twelve of the suspects used British passports, police said.
Six suspects used Irish passports, four used French passports, three used Australian and one used a German passport.
On Sunday, the British Embassy in Israel said it plans to talk to the British nationals whose identities were stolen and passports used.
"We have made contact with six of the individuals and look to locate the remaining six for the fraudulent use of their identities," an embassy official said Sunday.
The meetings will take place at the embassy, the UK Serious Organised Crime Agency said.
"We are arranging to speak to them as potential witnesses to a crime," a spokesman for the agency said.