Iraq's Foreign Ministry said it has summoned Turkey's top diplomat in Baghdad to protest cross-border shelling into northern Iraq.

A Foreign Ministry statement Saturday said the bombardment had started large fires and caused serious damage.  The Iraqi statement did not give details.

Turkey has been building up its forces along the border with Iraq.  The buildup is causing international concern Ankara might decide to send troops into northern Iraq to pursue separatist Kurdish rebels who use bases in Iraq to attack Turkish targets.

The Turkish military vowed Friday to crush Kurdish rebels, following the deaths of 12 soldiers in rebel attacks in eastern Turkey this week. 

The military's general staff said in an Internet statement that Turkish armed forces have "unshakable determination" to fight terrorism, and they will respond to attacks.

Eight Turkish soldiers were killed when rebels attacked the army post in Tunceli province Monday.  Four soldiers died in another attack Thursday.

The United States has warned Turkey against crossing the border.

The Kurdistan Worker's Party (PKK) has been fighting for autonomy in Turkey's mainly Kurdish southeast since 1984.  The violence has killed more than 30,000 people.

The United States, Turkey and the European Union classify the PKK as a terrorist group.

Some information for this report was provided by AFP and AP.