Turkish special forces pursued Kurdish guerrillas into northern Iraq and struck suspected targets with helicopter gunships and drones, killing at least five rebels, the military General Staff said in a statement.
Separately, two Turkish soldiers were killed on Saturday in two different explosions as they patrolled remote areas of Hakkari and Sirnak border provinces in Turkey, security sources said.
The raid into Iraq, which occurred in a border region south of Hakkari early on Friday, came after two other soldiers were killed by Kurdistan Workers Party (PKK) fire, according to the military command's website.
Three groups consisting of seven to eight commandoes each, as well as four helicopters and an unspecified number of unmanned aerial vehicles, made the incursion, it said.
"Anti-aircraft fire was opened onto helicopters from various positions across the border. The air force fired upon those areas," it said.
"It was observed that those positions were destroyed," it said, adding operations against the PKK continued.
Roj Welat, a PKK spokesman in northern Iraq, denied the military claim that five guerrillas were killed.
The Iraqi government has protested against previous Turkish land incursions aimed at rooting out the PKK. In February 2008, the military staged a ground incursion with 10,000 troops. It also regularly bombards suspected PKK targets from the sky.
The PKK took up arms against the Turkish state in 1984 in a conflict that has claimed 40,000 lives, mainly Kurdish.
The rebels, who are mainly based in Iraqi Kurdistan, say they are fighting for greater political rights for Turkey's estimated 15 million Kurds. The United States and the European Union both label the PKK a terrorist organisation.