An armed terrorist group opened fire Sunday at a an army officer's car in one of Damascus suburbs, killing two officers and injuring four army personnel, the state- run SANA news agency.

Brigadier Hasan Abdullah Ibrahim and first Lieutenant Yamin Khadour were killed while driving to the Electronic War department at Talfita area, just outside Damascus, said SANA, adding that another lieutenant colonel was injured along with three other army personnel who were riding with the brigadier.

The deadly attack came almost an hour after 11 people were killed in an attack targeting a passenger bus in central Homs province, according to private media reports.

The bus was transporting 14 passengers, including military personnel, when it came under fire, the report said, adding that three passengers managed to escape the gunfire and hide in a nearby storage, but were badly wounded.

The attack occurred at al-Fakhoura roundabout in Homs, when the bus was starting its trip to Damascus. Military personnel were among the injured, the report said.

Meanwhile, a law-enforcement member was killed and two civilians were wounded when an explosive device "planted by terrorists" went off near a military gas station in southern Daraa province on Sunday, according to SANA.

In another incident Sunday, a civilian worker at the traffic police department in Homs was killed and a law-enforcement member was injured when an armed group targeted a mini bus near the military hospital in the restive province.

The head of the so-called Syrian Free Army, a group of alleged army defectors who were given refuge in Turkey, has recently pledged to carry out attacks against army bases across Syria.

The Syrian government has blamed the incident as well as many others on terrorists and foreign-backed armed gangs.

Damascus said some 2,000 army and security personnel have been killed since the unrest began in March 2011, while the UN has reported more than 5,000 deaths from the Syrian violence.