Syrian government warplanes bombed Kurdish-held areas of the northeastern city of Hasaka on Thursday for the first time in the five-year-old civil war, the Syrian Kurdish YPG militia and a monitoring group said.
People's Protection Units (YPG) spokesman Redur Xelil said the air strikes had hit Kurdish districts of the city, which is mostly controlled by Kurdish groups, and the positions of a Kurdish security force known as the Asayish.
"There are martyrs and wounded," he told Reuters. The Syrian military could not immediately be reached for comment.
The YPG controls wide areas of northeastern Syria, where Kurdish groups have established an autonomous government, exploiting the unraveling of central state authority over the country since the start of the conflict.
The Syrian government still has footholds in the cities of Qamishli and Hasaka, both in Hasaka governorate, co-existing largely peacefully with YPG-held swathes of territory.
The cause of this week's flare-up was unclear.
Tensions erupted between pro-government forces and Kurdish groups in Hasaka on Tuesday, leading to the most significant violence between the sides since several days of fighting in Qamishli in April.
Xelil said government forces were bombarding Kurdish districts of Hasaka with artillery, and there were fierce clashes in the city.
The Syrian Observatory for Human Rights, which tracks the war using a network of activists, said warplanes had targeted Kurdish security forces' positions in the northwest and northeast of the Hasaka city.
The Observatory also said clashes were taking place in a number of positions around Hasaka.
Syria's complex, multi-sided war has created a patchwork of areas of control across the country, with parts controlled by the government, rebels, Kurdish forces and Islamic State.
The YPG makes up a significant portion of the U.S.-backed Syria Democratic Forces (SDF), a Kurdish and Arab alliance that fights against Islamic State insurgents in Syria.
Last week the SDF, backed by air strikes from the U.S.-led anti-IS coalition, said they had ousted Islamic State from the city of Manbij near the Turkish border after a two-month campaign.
(Writing by Tom Perry and Lisa Barrington; Editing by Mark Heinrich)
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