One teacher was killed in an armed attack in the Nusaybin town of Turkey's southeastern Mardin province on Tuesday, the semi-official Anatolia news agency reported.

Ersin Emiroglu, sub-governor of Nusaybin, was quoted as saying that an unidentified gunman or gunmen opened fire at Adnan Celik, a teacher of the Yavuz Selim Primary School in the Nusaybin town bordering Syria, as he was leaving the school.

Celik was killed on the spot and another teacher and three students were injured, said Emiroglu.

Earlier, a private Turkish TV channel reported that four students were wounded in the attack launched by an unidentified armed man.

Anatolia said investigations were underway, without giving further details.

The cause of the bloody incident remained unknown yet.

Meanwhile, Anatolia reported that Omer Akcura, who was injured in a bomb attack in Istanbul's Beylikduzu district last week, died of his wounds at hospital on Tuesday.

On Nov. 18, one person was killed and 10 others injured in an explosion near an overpass near Tatilya Entertainment Center in Beylikduzu district.

Anatolia quoted security sources as saying that a bomb placed in a trash can caused the explosion.

A string of bomb attacks have targeted Turkey's tourist destinations in recent months.

On Aug. 4, six people were slightly injured in two explosions in the southern province of Antalya, a popular tourist resort on the southern Mediterranean coast.

On July 16, a bomb went off in a bus in the seaside resort of Kusadasi, killing five people, including a British woman and an Irish teenager.

Source: Xinhua