Investigators are having problems identifying the fingerprints and DNA of the suicide bomber who killed six people in an attack on a bus in Bulgaria, Al Jazeera reported.
Bulgarian police, the FBI and Interpol are coordinating efforts to determine the identity of the suspect, who was caught wandering around on CCTV camera in the hour before the bus exploded at Burgas Airport, by the Black Sea.
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Five Israeli holidaymakers and the Bulgarian bus driver died in Wednesday's attack – which Israel has blamed both on Iran and the Iranian-backed Lebanese militant group Hezbollah.
The CCTV footage shows a casually dressed Caucasian male with long hair, wearing a blue baseball cap – who authorities say was carrying a fake US passport and a Michigan driver's license.
Bulgarian television identified the name on the license as Jacque Felipe Martin, born in 1987, of Baton Rouge, Louisiana. However according to the BBC, a witness to the attack said the man had dark skin, an Arabic accent and looked to be wearing a wig.
Bulgarian interior minister Tsvetan Tsvetanov said the man filmed at the airport appeared to be about 36 years old. With little clue to the suspect's identity, Tsvetanov could only confirm that he had been in the country for at least four days, and was not a citizen of Bulgaria.
Speaking on state television, Tsvetanov said the blast was caused by 6.6 pounds of TNT powder.
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Bulgarian prosecutors said the man had tried to rent a car in the days before the bombing but was turned down because his license appeared suspicious, the Huffington Post reported.
The owner of the car rental company confirmed the man she served was the same person from the CCTV footage, but said he had short, dark hair.
Funerals for the victims, one of whom was a 44-year-old pregnant woman, have been held in Israel and Bulgaria.