BEIRUT, Lebanon — The Syrian Army stormed the restive city of Dara’a with tanks and soldiers and helped detain dozens in towns across the country Monday in an escalation of the crackdown on Syria’s five-week-old uprising, according to residents and human rights activists. They said at least 25 people had been killed in Dara’a, with reports of bodies strewn in the streets.

The military’s move into the town seemed to signal a new, harrowing chapter in a crackdown that has already killed nearly 400 people. Until now the government has been hewing to a mix of concessions and brute force, but its actions Monday indicated that it had chosen the latter, seeking to crush a wave of dissent in virtually every province that has shaken the once uncontested rule of President Bashar al-Assad, 45.

“The government has decided to choose the path of violence and repression,” said a Syrian analyst in Beirut, who asked to remain anonymous for his safety. “How far can they go in this repression? That is the question.”

As in 1982, when it crushed an Islamist revolt and killed at least 10,000 people in Hama, the military again showed its willingness to use force to repress its own people. Though there were rumors of discord among soldiers, the leadership is still dominated by Mr. Assad’s minority sect, and its deployment to Dara’a illustrated that a crucial bastion of government support remained loyal — in stark contrast with Egypt, where the military’s refusal to fire on protesters proved decisive in President Hosni Mubarak’s fall.