At least seven Turkish soldiers were shot dead and three injured while on patrol in a mountainous area in the northern province of Tokat.
It is not clear who was behind the attack but suspicions have fallen on the banned Kurdish Workers Party PKK. However, PKK fighters usually mount attacks in southeastern Turkey's Kurdish region. It is possible that the attack was carried out by one of the extreme left-wing groups known to be active in northern Turkey.
The attack comes one day before a Turkish court will consider a move to ban the largest Kurdish party, the Democratic Society Party (DTP) for alleged links to a separatist group and coincides with a visit by Turkish Prime Minister Tayyip Recep Erdogan to Washington to meet US President Barack Obama. The NATO allies are scheduled to discuss various issues including improving the rights of Turkey's Kurdish minority.
On Sunday, a Kurdish student was shot dead during police clashes with protesters in the mostly Kurdish city of Diyarbakir. Around 15,000 Kurds marched through the streets of southeastern Turkey's largest city. Stones were thrown at police and the offices of the ruling AK a party was pelted with rocks. Anti-riot police used tear gas and water cannon to disperse the protesters.
The demonstration was organised by the PKK to support the claims of jailed PKK leader Abdullah Öcalan's claims of poor treatment in prison. Tensions in the region have risen as the DTP hearing approaches. The European Union has criticised the attempt to close down the party and has warned Ankara that a ban would violate Kurdish rights.