( AP ) - Authorities released four suspects Sunday who had been detained after a deadly bomb attack in a predominantly Kurdish city of southwest Turkey, a local official said.
The bomb, which had been packed in a parked car, exploded Thursday in Diyarbakir as a military bus carrying soldiers passed by. Five people were killed, including four high school students, and 68 people were wounded, including more than 30 soldiers.
No one claimed responsibility for the attack, but Turkish officials quickly blamed separatist Kurdish rebels. Prime Minister Recep Tayyip Erdogan said Saturday that the attack, in which plastic explosives were used, bore the hallmark of the rebel Kurdistan Workers' Party, or PKK.
Police detained four suspects, but gave no information about who they were or why they were suspected. An official said Sunday that the four had been released, but did not elaborate. The official spoke on condition of anonymity because he was not authorized to speak to the media.
The blast followed a spate of cross-border Turkish military operations into neighboring Iraq where rebels are based.
The PKK rebel group has waged a guerrilla war against Turkey since 1984 for autonomy in southeastern region, including Diyarbakir. The PKK is deemed a terrorist group by Turkey, the United States and the European Union.