According to reports from the city, an unknown number of security agents from different foreign countries have been detained or killed during the operation.
Syrian forces have inflicted major losses on the militants in Qusayr, destroying their weaponry and equipment.
The Syrian army has also found several caches of weapons, mostly containing israeli-made ammunition.
Qusayr, which is located in the central province of Homs, has been the scene of fierce clashes between Syrian forces and militants over the past few days.
The senior commander of the terrorist group al-Nusra Front, Abu Omar, was among those killed in battle on May 21.
The crisis in Syria began in March 2011.
Syrian President Bashar al-Assad said on May 18 that militants from 29 different countries were fighting against the government in different parts of the country.
President Assad also said in April that the situation in Syria was improving as the army enjoyed people’s support in the fight against terrorism.
The Syrian army said in a statement issued on May 21 that it had destroyed an Israeli military vehicle that drove toward the village of Bir Ajam, located in the Israeli-occupied Syrian territory of the Golan Heights.
Source: Press TV