The Syrian Observatory for Human Rights said the attacks took place in the city of al-Bukamal in Deir al-Zor province near the Iraqi border.
The monitoring group said the rebels captured 16 air defense personnel in their raid on the military facility.
An Observatory official, Rami Abdel Rahman, told the French news agency (AFP) seizing the air defense building was a "major coup" for the rebels. The group said the attack on the Hamdan military airport sparked violent clashes with government forces.
Opposition fighters have been carrying out a campaign targeting the government's air power.
A few days ago, Syrian rebels and government forces engaged in fierce fighting near a military airport between the northern cities of Aleppo and Idlib. Rebels entrenched in Aleppo and Idlib have targeted the Taftanaz military airport several times.
Syrian authorities blame the 17-month uprising on a foreign conspiracy and accuse oil-rich Gulf countries Saudi Arabia and Qatar, in addition to the United States and Turkey, of backing "terrorists" seeking to oust the government of President Bashar al-Assad.
Human rights groups have accused Assad's regime of committing many atrocities in its attempts to crush the uprising.
Some information for this report was provided by AP, AFP and Reuters.
