BEIRUT (AP) — Syrian activists say the Islamic State group has re-entered the historic city of Palmyra in central Syria, nine months after they were expelled by Syrian and Russian forces in a highly publicized campaign.

The activist-run Palmyra Coordination Collective reports Saturday that the militants seized the city's military warehouse and its northern and western neighborhoods after taking several government positions, oil fields, and strategic hilltops in the surrounding countryside in a lightning three-day campaign.

The Britain-based Syrian Observatory for Human Rights says the militants reached the city's Tadmor Hospital and its strategically located wheat silos.

The militants destroyed several of the city's famed ancient Roman monuments and executed its archaeological director after sweeping into the city in July 2015 and holding it for 11 months.