A suspected Kurdish militant claiming to have a bomb hijacked a passenger ferry carrying 21 people in northwest Turkey on Friday, local officials said.
Several coastguard vessels and a helicopter were tracking the ferry east of Istanbul in the Gulf of Izmit, they said.
The Kartepe ferry was carrying 17 passengers and four crew between Izmit and Golcuk when it was hijacked around 5.45 pm (3:45 p.m. BT), Kocaeli Governor Ercan Topaca said.
Some reports said there was only one hijacker but others said there were four or five assailants who had overpowered the captain of the ferry and seized passengers' mobile phones.
Security officials were not immediately available to comment on who was behind the hijacking but Kocaeli Mayor Ibrahim Karaosmanoglu said an assailant told the crew he was from the Kurdistan Workers Party (PKK) militant group.
The person hijacking the ferry said he was a member of the PKK and wanted to draw attention to it in the media, Karaosmanoglu told broadcasters.
Security forces were prepared for the possibility that the hijacker may want to take the vessel to nearby Imrali island in the Sea of Marmara, where PKK leader Abdullah Ocalan has been jailed since 1999, CNN Turk reported.
Don't intervene. I have a bomb. I will detonate it, it reported the hijacker as telling security forces.
Three coastguards and a helicopter were following the 400-passenger capacity ferry.
Kurdish, leftist and Islamic militants are all active in Turkey. More than 40,000 people have been killed in the PKK insurgency since the group took up arms against the state in 1984.
PKK guerrillas have staged a series of attacks on Turkish armed forces this year and killed 24 soldiers in an attack in Hakkari, bordering Iraq, last month.
That attack triggered cross-border operations by the Turkish military against the militants. Several thousand PKK fighters are based in the mountains of northern Iraq, from where they launch attacks on security forces in southeast Turkey.
A series of airplane hijackings have been carried out in the
last two decades but they have been rare in recent years and hijackings at sea are even rarer.
In January 1996, pro-Chechen gunmen hijacked a Black Sea ferry with 200 passengers on board and threatened to blow it up in protest at a Russian attack on Chechen separatists. Those hijackers surrendered three days later.
(Writing by Daren Butler; Editing by Sophie Hares)