ANKARA (Reuters) - Turkish President Tayyip Erdogan warned supporters of the pro-Kurdish opposition not to protest the military’s operation in northern Syria, saying security forces would intervene if they demonstrated.

“Know that wherever you go out on the streets our security forces are on your necks,” Erdogan said, referring to members of the pro-Kurdish Peoples’ Democratic Party (HDP), parliament’s second-largest opposition.

Erdogan was speaking to thousands of supporters in the northwestern city of Bursa. Turkish ground forces pushed into Syria’s Afrin province on Sunday, part of Ankara’s operation targeting a U.S.-backed Kurdish militia at its southern border.