At least seven people were killed and thirty injured on Saturday in a car blast in a busy market place in the rebel held Syrian town of Azaz near the Turkish border.
Residents and rescuers said the blast occurred during peak late night shopping after the breaking of the fast during the holy month of Ramadan.
"It's timing comes with heavy congestion by shoppers," said Yaseen Shalabi who was near the site of the explosion shopping with his family.
There was no immediate claim of responsibility.
The Arab-populated town run by Syrian rebel groups backed by Turkey opposed to Syrian President Bashar al Assad has been relatively quiet since it was hit by a car blast over two years ago.
Main towns in the north-western border area have in recent years been frequently hit by bombings detonated in crowded civilian areas.
Residents and rebels in the mainly Arab-populated rebel-held northwest have long suspected the Kurdish led YPG who control large swathes of areas in northeast Syria and east of the Euphrates in northern Syria. Others blame groups loyal to Assad.
The YPG have long denied such claims.
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