The Israeli army on Sunday launched a surprise military drill in the occupied Syrian Golan Heights, calling up thousands of reserve soldiers. “A short while ago, a large-scale surprise military exercise began in the Golan Heights area,” the army said in a statement. “In addition, as part of the exercise the system to call up reservists was activated,” it added. The Golan was turned into a "battlefield" during the exercises. There was an increase in ground vehicular activity and explosions were heard throughout the day. War brigades rushed from army bases deployed in Galilee and the Golan. Activities also spread to the Mediterranean, off the Israeli and Lebanese shores. The military announced that the drills would last for several days, but did not specify when they would end A military spokesman said the exercise was planned in advance as part of this year’s training schedule and is intended to maintain combat readiness. Israel has occupied most of the Syrian Golan Heights since the 1967 Middle East War. Sunday’s drill comes with Israeli Prime Minister Benjamin Netanyahu warning, during the regular cabinet session, from "the imminent Iranian threat in Syria" and promising firm actions against the Iranian position and Hezbollah. Also, Defense Minister Avigdor Liberman repeated on Sunday Israel’s position that it is “determined to prevent an Iranian presence in Syria, and we will do everything so that doesn’t happen. The danger on the northern border is serious and real.” Iran and Hezbollah are strong allies of Syria’s Bashar al-Assad regime, the forces of which have been fighting opposition groups in a deadly civil war since 2011. Since then, hundreds of thousands of people are believed to have been killed and millions more displaced by the conflict.