(CNN) -- The sound of heavy weapons and machine gun fire echoed through the night in the restive city of Al-Rastan after a large number of tanks moved in to block key roads and areas of town, an opposition activist said Monday.
"Several tanks have been in place since May at each of the entrances of the city, but Sunday a great number of tanks began blocking the agriculture parts of the town and the surrounding villages and even took positions inside Rastan," said the activist, a member of the opposition Local Coordinating Committees who could not be identified because of security concerns.
Elsewhere in Syria, security forces captured and killed two activists in Qosair, a town in Homs province, according to the Local Coordinating Committees, the activist group that has been organizing anti-government protests.
Students also continued their protests against the rule of Syrian President Bashar al-Assad, chanting, "No teaching, no learning until the fall of the regime" in Homs, Daraa and Damascus provinces.
In Al-Rastan, more than 50 tanks were in and around the city in the northwestern part of Homs province, said the activist, whose claims could not be independently verified.
The inflow of security forces means opposition groups are having trouble treating their wounded, the opposition activist told CNN.
"We have a major problem now that even though Rastan has one of the largest hospitals in Homs province we are unable to take our wounded out of fear of retaliation by security forces. Currently five to six tanks surround the hospital and we believe they may detain the wounded," the activist said.
People are scared to go to work in the area's industrial port because it has been surrounded by tanks and "just this week a young man was shot and killed by security forces," the activist said.
The Syrian government has been battling opposition activists for months in what the government calls a campaign against terrorists. At the United Nations, Foreign Minister Walid Moallem blamed "foreign incitement" for the troubles, which he said were fueled by U.S. and European sanctions.
"This course cannot in any way be reconciled with pronouncements about concern for the interests, security and rights of the Syrian people," Moallem told the General Assembly. "It further runs counter to the basic principles of human rights in defense of which these states base their interference in our internal affairs."
He said Syria had been "a model of peaceful co-existence" among its people's religious and ethnic groups, and that disturbing that peace was aimed at "spreading Western hegemony over the countries of the Mediterranean and serving Israel's expansionist interests."
On Monday, the state-run news agency SANA published a report citing an unnamed military source saying that authorities found Israeli weapons, explosives and stolen military uniforms in Homs and recovered weapons, ammunition detonators and other military supplies hidden in a drum and a water tank in the garden of a house in Naseeb, a city in Daraa province.
Military engineers also dismantled an explosive device next to Daraa University that could have killed more than 300 people, SANA reported.
Nearly 3,000 people have died in the government's crackdown, according to some accounts.
CNN's Salma Abdelaziz contributed to this report.