A former student opened fire at a high school in southeast Turkey on Tuesday, wounding at least 16 people before killing himself, an official said.

The 18-year-old attacker, armed with a shotgun, fired randomly at a vocational high school in Siverek, Sanliurfa province, before hiding inside the building.

He later killed himself with the same shotgun, Gov. Hasan Sildak said.

A teacher who was among the wounded was in serious condition, NTV television reported.

The motive remains unclear. School shootings are rare in Turkey.

Police special operations units were deployed after the assailant refused to surrender, while all staff and students were evacuated, NTV said.

Video footage showed dozens of students running out of the school toward the gate and onto the street.