ANKARA (AFP) - The Turkish army blamed the Syrian regime for an air strike on Thursday (Nov 24) in northern Syria that killed three soldiers and wounded 10, it said in a statement.

"In the air strike assessed to have been by Syrian regime forces, three of our heroic soldiers were killed and 10 soldiers wounded, one seriously," said the statement on its website.

The army said the strike took place at 3.30am (1230pm Singapore time). Turkish media reported earlier that the attack in the Al Bab region was by Islamic State in Iraq and Syria (ISIS) terrorists.

This is the first time the army has blamed President Bashar al-Assad's regime for an attack killing Turkish soldiers during Ankara's three month operation in northern Syria.

The Turkish military launched the operation - dubbed "Euphrates Shield" - in August supporting Syrian opposition fighters seeking to retake territory from ISIS in northern Syria with tanks and aerial support.

Hundreds of Turkish soldiers are taking part in the operation, which President Recep Tayyip Erdogan said this week was pushing forward with its aim of taking Al Bab from ISIS.

"We reached Al Bab right now and besieged it from the west," the president said in a speech on Tuesday (Nov 22).

The latest deaths raise to at least 15 the number of Turkish soldiers killed since Turkey began its operation in northern Syria.

Most were killed by ISIS, but one soldier was killed in an attack blamed on the Kurdish People's Protection Forces (YPG).