Erdoğan says militants retreated from Afrin

Turkish President Recep Tayyip Erdoğan said a group of fighters were forced to retreat from the border with Afrin in Syria after Turkey bombarded them with artillery fire.

"We will not allow this," Erdogan said at a press conference in Ankara, according to NTV television. "They will pay a very heavy price."

A group of about 10 trucks attempted to enter the enclave, Erdogan said, adding that sometimes "terrorists make their own decisions and they are wrong ones".

Syria said earlier on Tuesday that pro-regime forces entered Afrin to confront Turkish aggression and Islamic State (ISIS). It confirmed the Turkish bombardment, though said nothing about a retreat.