A car bomb killed at least nine people near a pro-Turkey rebel position in the northern Syrian city of Afrin on Sunday, according to a UK-based war monitoring group.

The Syrian Observatory for Human Rights said it was not clear who was responsible for the attack in the city, which was seized from Kurdish forces earlier this year.

The blast followed a threat by Turkish President Recep Tayyip Erdoğan on Wednesday to launch a new offensive against the Kurdish People’s Protection Units (YPG) in Syria.

The Observatory said the blast wounded dozens, and the toll was likely to rise.

“The car bomb exploded near a position of pro-Turkey fighters” in a market, killing five civilians and four fighters, Observatory chief Rami Abdel Rahman said.

At the site of the explosion, fresh herbs and vegetables were strewn on the ground near blackened market stalls.

Vegetable seller Abu Yazan al-Qabuni told AFP he was in the market towards midday when he saw a van enter.

“We thought it was carrying vegetables,” he said.

After a huge blast rocked the area, he ran to the site of the explosion, finding wounded people and body parts on the ground.

“I put them in a bag and buried them,” he said.

“There are no armed gangs, no terrorists here. We’re a vegetable market,” he added.

The city of Afrin was captured in March this year from the YPG by the Turkish military and Syrian rebels backed by Ankara.

Turkey accuses the YPG of being “terrorists,” but the Kurdish militia also forms the backbone of a US-backed alliance fighting ISIS in Syria.

YPG forces are present in areas along the Turkish border to the east of Afrin.

On Wednesday, Erdogan said Turkey was planning to launch a new offensive within the “next few days” against the YPG in northern Syria.

A day later, a Turkish soldier was killed in the Afrin region after coming under fire from the YPG, the Turkish Defense Ministry said.

– with reporting by Agence France-Presse