The shelling on Afrin, controlled by Turkish forces and its rebel allies, killed three people and injured a dozen more people, the medics and rescue workers told Reuters.
The separate rocket attack killed a woman and wounded three others in Maryamayn town on the outskirt of Afrin, they said.
Turkish forces responded by shelling Kurdish-held areas, media controlled by Turkey-aligned rebels reported, according to Reuters.
There was no immediate claim of responsibility for the attacks.
The city, which Turkey administers with the help of Syrian Arab rebels it backs, has in the last year been frequently hit by bombings detonated in crowded civilian areas.
Turkey has blamed previous attacks on the People’s Protection Units (YPG), which held the Afrin city until the Turkish military seized the region in a cross-border military operation in 2018.
The YPG has denied previous accusations of attacks on civilians. It says it only targets Turkish soldiers and their allies in a guerrilla campaign to drive out “occupiers”.
The YPG says Ankara wants to drive out Kurds and settle Arabs.
Turkey regards the YPG as a “terrorist group” tied to the Kurdistan Workers Party (PKK) inside its own borders, and has staged incursions into Syria in support of Syrian rebels to push it back from the Turkish frontier.
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