DAMASCUS, Syria (AP) — Rebels trying to topple Syrian President Bashar Assad’s regime battled army troops inside an air base in the north today as government forces fought opposition strongholds near the seat of his government in Damascus.

In Brussels, a NATO official said the alliance on Wednesday detected the launch of an unguided, short-range ballistic missile in the country, which is embroiled in a civil war that has killed more than 60,000 people in nearly 22 months.

The official, who spoke to The Associated Press on condition of anonymity in line with the alliance’s rules, also said Assad’s forces fired ballistic missiles at opposition-held areas twice earlier this month. The official said all the missiles were fired from inside Syria at unconfirmed targets in the north.

The alliance has condemned the use of such missiles, saying it disregards the lives of the Syrian people.

Syrian state-run SANA news agency said army troops were battling rebel units in several provinces around the country and in the suburbs of Damascus. The agency claimed troops were “inflicting heavy losses on the terrorists and destroying their weapons and ammunition.”

The Syrian government refers to rebels as terrorists.