A car boobytrapped with explosives detonated Thursday, wounding four people, in a northeastern Syrian town taken by Turkish-backed forces from Kurdish fighters during Turkey’s invasion, Syrian state media and a war monitoring group said.

The blast went off in the town of Tal Abyad outside the headquarters of a militia of Syrian fighters allied to Turkey, according to the SANA news agency and the Britain-based Syrian Observatory for Human Rights, which reported the injuries.

There was no immediate claim of responsibility for the bombing. Similar bombings have taken place in the past in another enclave held for several years by Turkey and its Syrian allies on the northwest part of the border. The Turkish-backed fighters are drawn from the ranks of Syrian rebels — many of them Islamic extremists — and are hated by both the Syrian government and Kurdish fighters.

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