Syrian opposition forces on Monday night reportedly captured the northern city of Al-Safira, which is close to many ammunition factories and what is believed to be the regime’s largest cache of chemical weapons.

The rebels took the city and, according to Al Jazeera, were only a mile away from the factories that produce a large percentage of the regime’s munitions.

Two weeks ago both sides traded accusations over the use of chemical weapons in Aleppo. Israel confirmed such weapons were used, but the US said it doubted the claims.

In Damascus, it appeared President Bashar Assad’s regime had started to fortify strategic buildings in an attempt to protect its headquarters in the capital, Al Arabiya reported.

Among the fortified buildings were symbolic structures as well as a prison holding criminals with a security background, the network said.