Galina Mileva, who was involved in the post-mortem examination, told BNT television on Sunday that the man "had a white face, light eyes, and very thick brown hair. The facial bones were shattered in the explosion."

Bulgarian police along with the CIA, FBI and Interpol are struggling to identify the bomber who carried out Wednesday's attack at the Black Sea town of Burgas which also claimed the life of the Bulgarian bus driver.

Bulgaria's Pressa newspaper and the bTV channel said the bomber could have had an accomplice who detonated the explosives by cellphone.

A man and his wife who ran a car rental service earlier said they recognised the suspect who came to hire a vehicle. They said he had a wad of 500-euro bills and refused to rent him a car as his US driving licence appeared to be a fake.

Bourgas prosecutor Kalina Tchapkanova quoted witnesses as saying the man "spoke English with a slight accent" and appeared to be Arab.

The car rental service owner's wife Afrodita Petrova said she was sure he was of Arab origin and had a shaven head.

But Bourgas journalist Katia Kassabova from the besove.bg website which carried the first images of the attack said Sunday that "the bomber is not the man who tried to rent the car. He could be an accomplice.

"The man who died had blue eyes while the man spotted in the car rental agency had brown eyes," she said, adding that the bomber was 1.82 metres (5.9 foot) tall.

Israel has blamed Iran and Tehran's "terrorist proxy" Hezbollah for the bombing, saying it fitted a pattern of other recent attacks or attempted attacks on Israelis including in Thailand, India, Georgia, Kenya and Cyprus.