GENEVA — Syria’s government said Wednesday that insurgents had assaulted two storage sites for some of the deadly chemical weapons components it has pledged to eliminate. It was the first time the Syrian authorities had reported such attacks in the three months since an international effort began to sequester and purge the country of the banned munitions.

Bassam Sabbagh, the Syrian representative to the Organization for the Prohibition of Chemical Weapons, the Hague-based group that is helping oversee the destruction of the Syrian arsenal, reported the attacks at the group’s executive council meeting, according to a European diplomat who was present. The diplomat spoke on the condition of anonymity because the meeting’s deliberations were private and the Syrian’s account was not publicly disclosed.

The attacks, if confirmed, underscore the difficulties in securing and destroying the chemical weapons in the midst of a civil war, a point that the organization’s officials have repeatedly made since an ambitious joint mission with the United Nations to eliminate them began in early October with the Syrian government’s consent.

The Syrian government is facing increased pressure to accelerate the process for ridding the country of the most dangerous materials among the 1,200 tons of toxic agents it has amassed over the years. It missed the deadline for exporting them by Dec. 31. The entire arsenal must be destroyed by June 30, under a Security Council resolution approved in September.