Reuters: cross-border violence between Syria and Turkey is becoming serious

The Turkish military returned fire after a mortar bomb shot from Syria landed in countryside in southern Turkey on Saturday. Reuters informs about this referring to the state-run Anatolian news agency.

It was the latest in a series of Turkish retaliatory attacks in response to mortar bombs and shelling by Syrian forces that have killed five Turkish civilians further east along the border.

The strikes and counter-strikes have been the most serious cross-border violence seen so far in Syria's conflict, and underlined how it could destabilize the region.

Turkish Prime Minister Tayyip Erdogan said on Friday his country did not want war but warned Syria not to make a "fatal mistake" by testing its resolve. Damascus has said the mortars landed in Turkey accidentally.

"Military units on the Turkish border launched retaliatory fire immediately," the agency said, without identifying its source or mentioning any casualties.