The casualty toll from the blast was not immediately known.
An Islamic Front commander said that his brigade dug a 850-metre
(2,800-foot) tunnel underneath Wadi al-Deif base, which is
surrounded by rebels but has remained inside government control for
the entirety of the three-year-long civil war.
Footage provided by the commander of the base, which stretches over
a large area of land, showed the ground balloon up before breaking
into a cloud of earth that engulfs the area.
The commander, who spoke on condition of anonymity, said he did not
know how many government soldiers had been killed but said it would
help rebels break into the base, which has been used for attacks in
the surrounding province of Idlib.
"Another attack like this and we won't even need to move in to take
the base," he said via Skype, adding that once rebels take the base
they would control all of the south Idlib, which is situated in
Syria's northwest bordering on Turkey.
Rebels fighting to overthrow President Bashar al-Assad regularly
carry out guerrilla attacks but have only started using large tunnel
bombs in recent weeks on military targets, including a hotel used by
soldiers in Aleppo last week.
The government boasts far superior firepower and its forces killed
more than 40 people, many of them civilians, in air strikes on
Wednesday, a monitoring group said.
Fifteen people were killed, including three from an emergency
medical team, during five air raids in Atarib in the northern
province of Aleppo, the Britain-based Syrian Observatory for Human
Rights said early on Thursday.
[to top of second column]
Four rebel fighters were killed by air strikes in the same area,
while 21 people, including women, were killed in air strikes on the
Sarmada area in Idlib, the anti-Assad monitoring group said.
Gunbattles, air strikes, car bombs, shelling and executions
regularly kill more than 200 people a day in Syria, where a conflict
that started as a peaceful protest movement has killed over 150,000
people and forced millions from their homes.
Despite the carnage and loss of swathes of territory in the north
and east to insurgents, Syria plans to hold a presidential election
next month that is all but certain to give Assad a third term.
Opponents have dismissed the vote as a farce.
(Additional reporting by Alexander Dziadosz and Oliver Holmes;
Editing by Mark Heinrich)
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