An Istanbul newspaper said security cameras filmed the suspected bombers, but local officials contacted by AFP either refused to comment or said the explosion in the town of Manavgat was due to a faulty gas canister.

Four people -- a Dutchwoman, a Hungarian, a Norwegian and a Turk -- were killed and 25 others injured in the blast on Sunday at the Manavgat waterfalls, a tourist attraction 60 kilometres (38 miles) east of Antalya, Turkey's biggest Mediterranean resort city.

The Firat news agency said on its website that an anonymous caller claimed the blast for the Kurdistan Freedom Falcons (TAK) and warned of more attacks against tourism targets.

"We have warned tourists to leave Turkey several times, we are warning them again," Firat quoted the caller as saying. "One cannot holiday in a place where there is war and conflict."

The popular daily Vatan said security cameras recorded three people, one of them a woman, placing a package inside a rubbish bin at the site about 20 minutes before the explosion.

Police refused to comment on the report.

Manavgat sub-governor Fikret Dayioglu told the Anatolia news agency that one of the foreign victims, initially said to be Russian, was identified Tuesday as a 42-year-old Dutchwoman whom Anatolia named as Femmie Merkusscha.

The other three victims have been identified as a Hungarian man, a Norwegian woman and a Turkish man who worked as a waiter at a restaurant in Manavgat.

Four other people remained under treatment in hospital Tuesday, Anatolia said.

Turkish officials say TAK is a front the separatist Kurdistan Workers' Party (PKK) uses for attacks on civilian targets while the PKK claims TAK is a splinter group over which it has no control.

TAK has claimed responsibility for several fatal bomb attacks in urban centers across Turkey since last year, the worst of them in the Aegean resort of Kusadasi, in which five people, including an Englishwoman and an Irish teenager, died in July 2005.

More than 37,000 people have been killed since 1984 when the PKK, listed as a terrorist organization by Turkey, the United States and the European Union, took up arms for self-rule in the country's mainly Kurdish southeast.

Tensions have escalated in the region since June 2004, when the group called off a five-year unilateral ceasefire.