"Over the last 15 days we have taken a number of steps and conducted consultations in Bosnia and Herzegovina as well as with our neighbours Serbia and Croatia," the Sarajevo-based daily Oslobodjenje of Tuesday cited Ahmetovic as saying.

Ahmetovic said the purpose of the investigation was to shed light on the circumstances of the attack. He added that Bosnian authorities would make a single register of suspects to make the fight against possible Islamic terrorism more efficient.

The country's different security agencies have so far had different lists of possible suspects, which has made their tracking difficult.

Apart from 23-year-old Jasarevic, three other people have been arrested and detained over the attack on the US embassy. The last to be arrested and placed in custody was Emrah Fojnica. During a search in the village of Gornja Maoca, near the northeastern town of Brcko, which is one of the seats of the Wahhabi community in Bosnia, the police found weapons and along with them an ID card with the name of Emrah Fojnica.

Oslobodjenje reports that Fojnica earlier threatened its reporter Esad Hecimovic who wrote a number of articles warning about the danger of the Wahhabi community's activities.

Judging by Fojnica's Facebook profile, he is linked to Egyptian Imad al-Misri, who at one time was the leader of the Wahhabi community in Bosnia before he was arrested in 2001 and deported.

Dnevni Avaz daily of Tuesday says that during their visit to Bosnia, agents of the U.S. Federal Bureau of Investigation tried to talk to the four men charged with the attack on the U.S. embassy.

Attorney Idriz Kamenica, who represents Munib Ahmetspahic, suspected of aiding Jasarevic, confirmed that FBI agents forwarded a request through prosecutor Dubravko Campara to interview his client, but he refused it, saying that it would constitute interference in Bosnia's sovereignty.