An explosion near a courthouse in the western Turkish city of Izmir killed two people and wounded at least five more, Turkish media reported Thursday, January 5.

The private Dogan news agency reported that the explosion was caused by a car bomb in front of the courthouse. A police officer and a courthouse employee were killed. After the explosion police exchanged gunfire with three suspected assailants, two of whom were killed, USA Today reports.

It was not immediately clear if a third person was at large.

Local authorities told The Associated Press that it appeared that the Kurdistan Workers’ Party, or PKK, an outlawed militant group, was behind the attack. There has been no confirmation.

The incident comes as Turkey is on high alert following a nightclub attack in Istanbul during New Year’s celebrations that left 39 people dead. The Islamic State group claimed responsibility for that attack. The suspected attacker has not been captured.

Turkey said it has identified the suspected gunman who opened fire on the crowded nightclub, but it has not named him. Police have released a photo of the suspect. Authorities believe he may be from Central Asia or a Chinese Uighur, a Muslim ethnic group.