IS launches new assault on besieged eastern city in Syria

FILE - This file frame grab from video provided on Sunday, Dec. 25, 2016 by Step News Agency, a Syrian opposition media outlet that is consistent with independent AP reporting, shows smoke rise from the government forces shelling on Wadi Barada, northwest of Damascus, Syria. Opposition activists and Syria's state TV said on Friday, Jan. 13, 2017 that maintenance workers have arrived in the rebel-held valley near Damascus to fix the water facility there, ending a violent standoff that has dried out the capital for weeks. (Step News Agency, via AP, File) (The Associated Press)

Syrian opposition activists say Islamic State militants have launched a new offensive on government-held areas in the contested eastern city of Deir el-Zour.

They report intense fighting Saturday between Syrian troops and IS members in the city and in the vicinity of a nearby military airport controlled by government forces.

The extremists, who control most of Deir el-Zour province, have kept the provincial capital under siege since 2014. Government forces have withstood the encirclement thanks to air-dropped humanitarian assistance and weapons and ammunition flown into the airport.

The Syrian Observatory for Human Rights says Saturday's offensive was the most intense attack in a year. Others reported loud explosions that shook the city and said Syrian warplanes were taking part in the battles.