Two new computer-generated images of the alleged perpetrator of the terrorist attack in Bulgaria's Black Sea city of Burgas have been prepared.

The Bulgarian daily Pressa (Press) writes that the new portraits are more clear and precise than the one released right after the deadly incident. The newspaper stresses that images have not yet been officially released and they are the only ones to have them.

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 main lead so far was that it has been executed by a suicide bomber, who arrived from abroad.

The assailant is pictured with long and short hair since he used both looks while moving around the airport. His head, which was found 63 meters away from the location of the blast, has been patched piece by piece and used as a model for the new images, according to Pressa.

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

The investigators hope these new portraits will help them find more witnesses.

Meanwhile, the initial lead that the man has been a suicide bomber 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.

The forensic team is also testing blood from the suspect's leg for narcotics content in order to verify the lead that he has been deluded, used as a mule, and acted under the influence of illegal drugs.

Just one day earlier, the former Chief of Israel's Counter-Terrorism Bureau, Brigadier General Nitzan Nuriel, also stated that the perpetrator of the terrorist attack was not a suicide bomber.

Speaking in an exclusive interview for Darik radio, the General said the people who hired the suspect have lied to him and he had no idea that he was going to die.