The confiscation of the weapons shows the large scale of army operation in the western city which borders Lebanon.
The militant groups had also dug several underground tunnels to be used as shelters within very hard situation.
Nearly all the supply routes to the terrorist al-Nusra Front forces are cut following Syrian army’s successful operation in retaking the town.
The army said the "victory in al-Qusayr is a clear message" to what it called enemies of Syria, mainly Israel and "its agents in the region," the state news agency SANA reported.
Al-Qusayr is near the highway that connects the capital Damascus with the government-held coastal cities of Latakia and Tartous. The militant groups used the town as a supply route from Lebanon.
The rebel-linked Coordination Committee of al-Qusayr confirmed the retreat by militant forces from the town.
"In the face of an enormous arsenal, the fighters had to withdraw due to a lack of supplies," the group posted on Facebook.
The main opposition Syrian National Coalition also warned of the potential for "horrendous and mass massacres" after the takeover.
Hezbollah party's deputy chief Sheikh Naim Qassem declared the victory in al-Qusayr a "serious blow" to America, Israel, and extremist militant groups.
