Officials in Turkey say suspected Kurdish militants clashed with police before detonating a car bomb in the western city of Izmir.
A police officer and a court employee were killed, along with two of the suspected attackers.
Ten people were injured.
The attackers’ car was stopped at a checkpoint near the city’s main courthouse.
This sparked a confrontation with the police. A car bomb was subsequently detonated.
Izmir police shot dead two of the attackers and are hunting a third, according to the state-run news agency Anadolu and police sources.
Two people believed to have sold the vehicle used in the attack to the assailants have reportedly been detained.
A second vehicle was destroyed in a controlled explosion.
Police reportedly think the attackers had planned to use it to escape.
The explosion and gunfire outside the main courthouse in Izmir have highlighted Turkey’s deteriorating security situation.
It comes five days after a gunman killed 39 people in a New Year’s Day mass shooting at a nightclub in Istanbul.
Much larger attack thwarted – officials
Deputy Prime Minister Veysi Kaynak said a much larger attack was apparently being planned.
This was based on the weapons found at the scene in Izmir.
The local governor said the arms included Kalashnikov rifles, hand grenades and ammunition for rocket-propelled grenade launchers.
Who was behind the attack?
Izmir governor Erol Ayyildiz says initial findings suggest that Kurdistan Workers Party (PKK) militants were behind the attack.
NATO member Turkey is part of the US-led coalition fighting ISIL in Syria.
It is also battling an insurgency by the PKK in the mainly Kurdish southeast.
Ankara regularly targets PKK camps in northern Iraq.
Its military operations in Syria also aim to stop Kurdish militias it sees as an extension of the PKK from gaining territory there.
There was no immediate claim of responsibility for the attack in Izmir.
The liberal coastal city has largely escaped the violence that has plagued Istanbul and the capital Ankara in recent months.
What they are saying
“Based on the preparation, the weapons, the bombs and ammunition seized, it is understood that a big atrocity was being planned,” – Deputy Prime Minister Veysi Kaynak.