At least 8 people, including children, were killed in Syrian regime air strikes on a school sheltering displaced people in southern Daraa province, local activists said in an initial death toll.
The Wednesday's strikes hit Tafas town in the western countryside of Daraa.
Meanwhile the National Defense, local rescuing group, is working to save wounded people.
The regime army and Iran-backed Hezbollah militia have escalated attacks against a rebel-held part of the southern city of Daraa, a possible prelude to a large-scale campaign to wrest full control of the city, rebels and residents told Reuters.
The intensive raids and bombing strikes mainly pounded the southern part of Daraa, strategically located on the border with Jordan and where the uprising against Bashar al-Assad erupted six years ago.
In the city of Daraa, regime warplanes carried out more than 12 raids since early morning.
The Assad army, also, has recently intensified dropping barrel bombs, drums or cylinders packed with shrapnel, and has fired hundreds of so-called elephant rockets on Daraa's old quarter and a former refugee camp nearby, rebels and residents said