British special agents have taken DNA of the suspected suicide bomber who killed six people at the airport near Bulgaria's Black Sea city of Burgas in an effort to determine if he came from the UK.

The information was announced by the British Daily Mail.

According to the publication, security service officials travelled to Bulgaria and took samples from the disembodied corpse and dental samples of the alleged perpetrator of the terror attack.

On Friday, after two new computer-generated images of the man were released, a new lead that he may have been British or have been living in the UK before launching the attack emerged.

The Bulgarian investigative site Bivol.bg also published photos of the reconstructed head of what was believed to have been the suicide bomber.

Witnesses of the attack say there was a second accomplice.

Meanwhile, the Bulgarian Standard daily reported Saturday that the suspect had toured at least ten cities across the country. The paper cites unnamed sources from the investigation informing that 20 witnesses have called the Interior Ministry, after the picture was released, to report they have spotted the man. Their accounts, however, are said to be contradictory, particularly when it comes to the description of the assailant. Nevertheless, all have reported that he wore shorts and a black sweatshirt.

The authorities decline giving official information about the whereabouts of the individual in question in the days before the attack, but from the Friday behind-closed-doors hearing of Interior Minister, Tsvetan Tsvetanov, in the Parliament, it emerged that the assailant has visited the cities of Varna and Plovdiv.

The July 18 terrorist attack in Bulgaria's Burgas, also known as the Burgas Bus Bombing, killed 5 Israeli tourists and a Bulgarian bus driver at the Sarafovo Airport. The initial lead was that it has been executed by a suicide bomber, who arrived from abroad.

This lead, however, is looking less and less reliable. One of the reasons is that the bomb is different from those used by suicide bombers, who aim to cause the most damage possible. It was not made with nails and steal balls, which inflict large-scale destruction.

Results from blood testing from the suspect's leg for narcotics content are expected in order to verify the hypothesis that he has been deluded, used as a mule, and acted under the influence of illegal drugs.

The head will be sent to the capital Sofia shortly to be examined by anthropologists, who hope to determine the nationality and origins of the man.