BEIRUT (AP) — Syrian opposition activists say a woman has blown herself up, killing two people, outside an administration office for an al-Qaida-linked group in the northern city of Idlib.

The Local Coordination Committees say Tuesday's blast outside the offices linked to Hayat Tahrir al-Sham also wounded others. The attack comes weeks after the al-Qaida-linked group captured wide parts of northern Syria in battles with Turkey-backed opposition fighters.

The Britain-based Syrian Observatory for Human Rights, another group monitoring the civil war, said the bomber exchanged fire with guards before blowing herself up.

Idlib, in northwestern Syria, is the last stronghold of opposition groups fighting President Bashar Assad's government. The al-Qaida-linked HTS is a dominant force in the area.

A Russian and Turkish-backed cease-fire is in place since September but has increasingly been violated.