Al Mayadeen said Islamic State groups unexpectedly came into the rear of the Syrian army which is pressing the advance into the Syrian desert and eastwards to the border with Iraq after it has liberated Palmyra, TASS writes.

According to the television channel, government forces are trying to drive Islamic State gunmen from the positions they have seized. The army is backed by the Syrian air force.

Al-Shaer is considered Syria's biggest gas field. The government army has been defending it from Islamic State since 2014. The field is of strategic importance for the Syrian economy. Gas from this field is supplied to heat stations in Homs and Damascus which generate electricity for Syria's central and southern provinces.