BEIRUT, Oct 11 (Reuters) - At least four people were killed when a car bomb exploded in the Syrian city of Afrin on Monday, a medical source said, the latest such attack in the northwestern region that is controlled by Turkey and Syrian rebels it supports. The blast wounded another six people, the source said. Turkey has blamed previous bomb attacks in Afrin on the Syrian Kurdish YPG group, which held the Afrin area until Turkish forces seized the region in a cross-border military operation in 2019. read more Turkey regards the YPG as a terrorist group tied to the PKK inside its own borders, and has staged incursions into Syria in support of Syrian rebels to push it from the Turkish frontier. The YPG views Turkey as an invader and occupying force.