DIYARBAKIR, Turkey (Reuters) - Kurdish militants set off a roadside bomb that killed four Turkish police officers as they traveled in an armored vehicle in the southeast of the country on Thursday, officials said.
Militants of the Kurdistan Workers' Party (PKK) have mounted daily attacks against security forces since a two-year ceasefire ended in July. Roadside bombs are a common PKK tactic.
The attack occurred as the police officers joined the local fire brigade in traveling to the scene of a fire which PKK militants were believed to have started in a school, according to the governor's office in Mardin province.
Turkish warplanes bombed PKK positions on Wednesday after one soldier was killed in the same region. State media said 20 militants were killed in those air strikes.
More than 70 members of Turkey's security forces have been killed since the wave of PKK attacks began in late July, when the government also launched air strikes on the group's camps in northern Iraq.
State-run Anadolu Agency says more than 900 PKK militants have been killed in that period in southeast Turkey and Iraq.
The PKK, designated a terrorist organization by Turkey, the United States and European Union, took up arms in 1984, and more than 40,000 people have been killed.
The violence halted after Ankara began talks with the group's jailed leader, Abdullah Ocalan, in 2012.