Eight Turkish soldiers and 21 militants of the outlawed Kurdistan Workers Party (PKK) were killed on Friday, according to the military and media reports, as violence in the largely Kurdish southeast widened a day after two bombings.
After the collapse of a ceasefire between the PKK and the government last July, Turkey's southeast has seen some of its worst violence since the height of the Kurdish insurgency in the 1990s.
Six soldiers were killed and eight were wounded in clashes with militants in the southeastern Hakkari province, the military said in a statement.
Two more soldiers were killed in a separate incident when a military helicopter crashed in Hakkari due to a technical fault, the military said. Six PKK militants were also killed in an operation in that region, it said.
Fifteen militants were killed in clashes in Sirnak province, broadcaster NTV reported, citing the Turkish military.
On Thursday, four suspected bomb makers were killed and 17 people wounded when an explosion ripped through a village in the southeast as PKK militants loaded explosives onto a small truck, the government said.
That blast was just hours after an explosives-laden car blew up near a military base in Turkey's biggest city, Istanbul, wounding six soldiers and a civilian.
No one has claimed responsibility for Thursday's bombing in Istanbul.
Turkey has suffered a series of bombings this year, including two suicide attacks in tourist areas of Istanbul blamed on Islamic State and two car bombings in the capital, Ankara, which were claimed by a PKK offshoot.
The Kurdistan Freedom Hawks (TAK) says it has split from the PKK, which has waged a three-decade insurgency against the Turkish state, but experts who study the two militant groups say they retain close links.