At least one man has been killed by sniper fire in a suburb of the Syrian capital and security forces pursuing a deadly crackdown against President Bashar Assad’s critics stormed villages, raiding houses and making arrests, activists said on Sunday.

The targeted villages were in the eastern Deir el-Zour province. Arrests also were reported in the northern Idlib province. Intermittent gunfire erupted in several areas across the country.

Syria’s Interior Ministry urged residents of the capital not to respond to calls posted on social media networks to stage protests in Damascus squares “for their own safety” after some of the most intense protests there since the start of the five-month uprising against Mr. Assad.

Human rights groups say Mr. Assad’s forces have killed more than 2,000 people since the uprising erupted in March, touched off by the wave of revolts sweeping the Arab world.

Central Damascus has been largely quiet in comparison with other major cities. On Saturday, Syrian forces fanned out in the capital and its suburbs to prevent protesters from converging on the centre of Damascus.

Activists said security forces fired live ammunition and beat up protesters emerging from the al-Rifai mosque in the Kfar Sousa district of the capital on Saturday after they tried to stage a protest, wounding many. They included the mosque’s preacher, Osama al-Rifai.

The attack triggered sit-ins and protests in several other parts of the capital and its suburbs on Saturday and overnight.

Intense protests in Damascus and Aleppo, Syria’s two largest cities and economic powerhouses, would pose a real threat to Mr. Assad.

The Local Coordination Committees, an activist network, and the London-based Syrian Observatory for Human Rights said in statements on Sunday that snipers shot dead one man in the Damascus suburb of Saqba overnight after troops deployed in the restive area.

Mr. Assad has met the extraordinary revolt against his family’s 40-year dynasty with a brutal security crackdown, but has also acknowledged the need for reform. He has lifted decades-old state of emergency laws and this month endorsed new laws that would allow the formation of political parties alongside the ruling Baath party and enable newly formed political parties to run for parliament and local councils.

On Sunday, he endorsed a new media law that would restrict government censorship of local and foreign publications and end government control over the media.

The opposition dismisses those changes, once key demands, as too little too late.

The uprising has left Mr. Assad with few international allies — with the vital exception of Iran, which the U.S. and other nations say is helping drive the deadly crackdown on dissent.

Iran said on Saturday that a power vacuum in Damascus could spark an unprecedented regional crisis while urging Mr. Assad to listen to some of his people’s “legitimate demands.”

In an emergency meeting on Syria that ended early Sunday in Cairo, the Arab League decided to send its leader, Nabil Elaraby, to Damascus to seek a solution. In a statement, the league expressed “grave concern” over the bloodshed in Syria.

More In: International | News