A Turkish court on Monday charged three more suspects in connection with a deadly car bomb attack here earlier this month, judicial officials said.
The three men detained earlier, relatives of the suspected bomber in the January 3 attack, were charged with aiding the assailant, who has been jailed pending trial along with six others, the sources said.
Police say the main suspect, allegedly a Kurdish militant, confessed to detonating the remote-control bomb on orders from the separatist Kurdistan Workers' Party (PKK) in retaliation for Turkish air strikes on PKK camps in neighbouring Iraq since mid-December.
The trial will begin after prosecutors draw up an indictment detailing the charges against the suspects.
The attack killed seven people, six of them teenagers attending classes at a nearby private school in central Diyarbakir, and left 66 injured, about half of them military officers.
The intended target was apparently an army bus passing by with several dozen soldiers on board close to a military facility in this city, the biggest in Turkey's mainly Kurdish populated southeast.
The PKK, listed as a terrorist group by Ankara and much of the international community, has apologised for the attack and put the blame on Kurdish militants acting without the approval of the leadership.
The Turkish army has confirmed four air raids conducted with US intelligence assistance against PKK camps in northern Iraq since December 16 in which it said at least 150 rebels were killed and more than 260 PKK positions destroyed and the rebels had threatened to retaliate.
The PKK has waged a bloody campaign for self-rule in southeast Turkey since 1984. The conflict has claimed more than 37,000 lives. (AFP)