Two rebels belonging to the Kurdistan Workers' Party (PKK) were killed Friday night by security forces in a mountainous district in the province of Sirnak, neighbouring Iraq.

Four other PKK members were killed Friday in the province of Van, close to Iran, in an operation in which four members of the security forces were injured, one of whom died Saturday from his wounds, the Anatolia news agency reported.

A second soldier died Friday in Sirnak when the helicopter in which he was travelling came under fire.

The Turkish army has intensified its operations against the PKK, regarded as a terrorist organisation by Turkey, the European Union and the United States, after the deaths of 15 members of the security forces in the past week in the southeast of the country.

Ankara has raised the possibility of making military incursions into northern Iraq to destroy the many PKK camps there if the United States and Iraq do not themselves take steps against the rebels.

Since the PKK began its separatist rebellion in 1984 some 37,000 lives are estimated to have been lost.