The governor of the southern province of Sanliurfa dismissed early reports that the gunfire had come from across the frontier in Syria, saying instead that the on-duty soldier had killed two of his colleagues patrolling near the Ceylanpinar border crossing just after midnight local time (2200 Monday UTC) and then shot himself. The three soldiers died close to where the "Islamic State" has battled Kurdish fighters, initially bringing up the possibility of stray bullets, which have crossed the border in the past, or even deliberate targeting by a faction within Syria.

"According to the evidence we have collected, it was not a terrorist incident but a soldier guarding the border running amok and killing his friends and then himself," Sanliurfa Governor Izzettin Kucuk told reporters on Tuesday.

Turkish soldiers were able to watch the battle for Kobani

Turkey has frequently seen spillover from Syria's nearly four-year civil war, with soldiers shot at and mortar rounds landing across the border. The country also hosts a number of Syrian refugees in the region, one of a few nations to take in those who have fled the war en masse.

Earlier this year, near the same crossing, Turkish soldiers reportedly clashed with alleged members of the outlawed Kurdistan Workers' Party, leaving several people dead. That incident also appeared to involve cross-border smugglers.

mkg/rc (Reuters, dpa)