Soldiers reinforced patrols and checkpoints Friday following a rare nighttime curfew imposed by authorities seeking to quell escalating clashes between factions supporting the Western-backed government and Hezbollah protesters trying to bring it down.

The order to clear the streets — lifted just before dawn — came after rival groups turned a university campus into a battle zone on Thursday with at least three people killed when mobs faced off with homemade clubs and stones.

Army officers reported snipers opening fire during the melee, but there was no clear indication of whether the gunmen were acting on orders from any of the leaders locked in the deepening standoff or saboteurs seeking to inflame the situation.

Yet all sides recognized that the country could be stumbling dangerously in the direction of civil war. Government officials and Hezbollah's leader, Hassan Nasrallah, appealed for calm and allowed security forces to enforce the first blanket curfew in the Lebanese capital in 11 years.

Walid Jumblatt, a senior pro-government politician, called on the Hezbollah-allied speaker of parliament to reconvene lawmakers in an attempt to restore dialogue between the feuding sides.

Talks between the Shiite Muslim-led Hezbollah and the government of Prime Minister Fuad Saniora broke down in November over Hezbollah's demands for greater power — riding their near hero status in Lebanon after humbling far superior Israeli ground forces in last summer's war.

Hezbollah has kept up relentless pressure on Saniora's embattled administration, which is backed by Sunni Muslims and smaller Christian allies. On Tuesday, roadblocks by Hezbollah and its opposition allies brought most of Lebanon to a standstill.

The showdown has again forced Lebanon's patchwork of religious groups and factions to chose sides — as they did during the devastating 1975-90 civil war.

Then, it was mostly Muslims against Christians, who represent more than a third of Lebanon's 4 million people. Now, it's a power struggle pitting Sunnis and Shiites — and again making Lebanon a stage for wider proxy struggles in the Middle East with Iran and Syria backing Hezbollah, and Washington and allies such as Egypt and Saudi Arabia hoping to keep Saniora in power.

"There are some in Lebanon — encouraged by outside forces, I might add — who would like to distract attention away from the government of Lebanon's accomplishment," said a statement from the U.S. ambassador to Lebanon, Jeffrey Feltman, in a reference to major pledges of aid made at an international donors conference in Paris on Thursday.

Saniora carries home promises of $7.6 billion to help rebuild the war-battered nation. But he returns to a country that appears less stable with each passing day.

Security forces planned close watch over the planned funerals for the victims of the clashes at Beirut Arab University for any sign they could spark another round of unrest. Nearly 170 others were injured in the mayhem. All schools and universities were ordered closed Friday by the education minister. Classes were scheduled to resume Monday.

Cleaning crews gathered piles of debris, broken glass, tear gas canisters and military bullet casings from the streets around the university on the southern edge of the city. Dozens of smashed and burned cars were towed away as residents returned to survey the damage.

Stores reopened in many parts of the city, but traffic appeared lighter as many people chose to remain home and schools were closed.

In Paris on Thursday, Saniora pleaded to his countrymen to "distance themselves from tensions."

"No one can help a country if the people of this country don't want to help themselves," he said. "I call on your wisdom and reason."

Nasrallah — who has insisted in recent days he does not want Lebanon to tumble into civil war — told followers it was a "religious duty" to get off the streets to allow security forces to keep order.

"Nobody should be surprised when things start to spin out of control," the U.S. Ambassador Feltman said in an interview with Alhurra, the U.S. government-funded Arabic-language satellite television network that broadcasts to the Middle East.

He said he suspected Syria — which backs Hezbollah and controlled Lebanon for nearly three decades — was behind the current troubles, but did not provide any evidence.

There was no immediate reaction from Syrian officials. A woman who answered the phone at the Syrian U.N. mission in New York said nobody was available to speak to the media.