BEIRUT — Syrian security forces opened fire today on protesters and hunted them down in house-to-house raids, killing about 30 people in the deadliest day in weeks in the country’s 7-month-old uprising, activists said.

The popular revolt against Syrian President Bashar Assad’s regime has proved remarkably resilient, with protests erupting every week despite the near-certainty the government will respond with bullets and tear gas. The U.N. estimates the regime crackdown on the protests has killed 3,000 people since March.

Much of the bloodshed today happened after the protests had ended and security forces armed with machine guns chased protesters and activists, according to opposition groups monitoring the demonstrations. Authorities disrupted telephone and Internet service, they said.

The Syrian opposition’s two main activist groups, the British-based Syrian Observatory for Human Rights and the Local Coordinating Committees, gave figures for the protesters killed on Friday ranging from 29 to 37.