A roadside bomb has rocked a bus carrying military personnel and their families in Turkey's largest city, Istanbul, killing four people and injuring a dozen.
It follows a step up in the Turkish army's operations against Kurdish rebels.
The remote controlled bomb was detonated near a military housing complex.
Three of those killed were sergeants and the fourth was a 17-year-old girl.
No group has claimed responsibility for the explosion but the blast comes days after the separatist Kurdistan Workers' Party - the PKK - threatened to launch attacks across Turkey, the BBC reports.
Fighting has recently intensified between Turkish military forces and the PKK, which killed 11 soldiers at the weekend.