An explosion on a minibus in the Turkish Aegean resort of Kusadasi is reported to have killed at least four people and injured 14 others.

The blast comes six days after a bombing in the nearby town of Cesme, which left at least 20 people injured.

The cause of Saturday's explosion is not yet known, but police have not ruled out a suicide bomb attack.

Kurdish guerrillas said they carried out a bomb attack in Kusadasi in April, in which one policeman was killed.

Militants both from the far left and from Islamist circles have carried out bombings in Turkey in the past, as have Kurdish rebels.

If Saturday's minibus explosion is a bombing - and everything points to it - then Kurdish paramilitaries are the most likely suspects, the BBC's Jonny Dymond in Istanbul says.

A group called the Kurdish Liberation Hawks (Tak) said it carried out the bombing in Cesme on 10 July.

The Tak is an offshoot of the Kurdistan Workers' Party (PKK), which has been fighting the government for independence since 1984.

More than 37,000 people have been killed since.

The rebels declared a unilateral truce in 1999, but ended it in 2004, saying Turkey had not done enough to meet their demands.

PHOTO CAPTION

A Turkish police officer investigates the scene as an injured woman waits for medical care following an explosion in the western Turkish resort town of Kusadasi July 16, 2005. (REUTERS)