Three suspects detained in connection with last week's suicide bombing in Istanbul's Sultanahmet district were referred to court for arrest on Tuesday.

Earlier this week six people, including foreigners, were detained in connection with the bombing. Some foreign nationals were among those questioned by prosecutors, with Turkish media reporting that they included Chechen nationals.

Kenan Kumaş, a police officer on duty at a police station near the historical Sultanahmet (Blue Mosque) Square was killed and another policeman was injured when a woman carrying explosives blew herself up at the police station.

Conflicting reports emerged following the bombing last Tuesday, which was initially blamed on the terrorist organization the Revolutionary People's Liberation Party-Front (DHKP-C). The organization claimed responsibility for a foiled attack at an Ottoman-era palace in the city earlier this month, and announced that its member, Elif Sultan Kalşen, was the suicide bomber.

However, Kalşen's family could not identify the body of their daughter at the coroner's office. Days later amid rumors circulating that the bomber was actually a Russian woman of Chechen origin going by the name of Diana Ramazova, the DHKP-C retracted its statement claiming responsibility.

Interior Minister Efkan Ala has said that the assailant had been identified but did not name her.

Rumors of the woman's nationality raised concerns that she may be part of Shahidka, the infamous Chechen female suicide bombers who have targeted Russia in the past in retaliation for Russia's crackdown on Chechen dissidents. Turkey maintains good relations with Russia, but it also provides shelter to a considerable number of dissidents opposing the pro-Russian regime of Chechnya and the Kremlin's crackdown on the insurgency.