A powerful truck bomb blast claimed by Islamic State killed nearly 50 people and wounded scores more in the northeastern Syrian city of Qamishli near the Turkish border, a monitoring group and state television reported.

The attack, near a Kurdish security forces headquarters, was the deadliest of its kind in the city for years, the British-based Syrian Observatory for Human Rights said.

The blast killed at least 48 people. The death toll expected to rise because of the number of people seriously injured, the Observatory said. State media put number of dead at 44.

State TV showed footage purportedly from the scene of one blast, showing large-scale damage to buildings, vast amounts of rubble strewn across the road and plumes of smoke rising.

The explosion was so powerful it shattered the windows of shops in the Turkish town of Nusaybin, directly across the border. Two people were slightly hurt in Nusaybin, a witness said.

Kurdish forces control much of Hasaka province, after capturing vast areas from the jihadist group last year.

The Kurdish YPG militia, which has proved the most effective partner for a U.S.-led coalition battling Islamic State, is also involved in fighting the extremists farther west, in Aleppo province.

Islamic State claimed responsibility for what it said was a suicide truck bomb attack, and added that it targeted Kurdish security forces.

The group has carried out a number of bombings in Qamishli, in Hasaka province, and in the provincial capital, Hasaka city.