In Beirut, government supporters and opponents clash

The fighting began with opponents of the government setting tires ablaze to block the city's main roads, notably those leading to the international airport, where flights were suspended. Protesters said they were answering a call by labor unions to oppose government policies aimed at combating inflation, but the unions in the end canceled a planned march because of the chaos.

Tensions quickly took on a political character, with Sunni Muslim backers of the government and Shiite Muslim opposition supporters amassing in their respective neighborhoods and hurling stones at each other. Gunfire erupted in mixed Shiite-Sunni districts. Armed fighters with the Hezbollah-aligned Amal movement and the pro-government Future Movement stood on the corners of empty streets.

"I saw a lot of men armed with Kalashnikovs," said Jaber, a witness who asked that his last name not be published. "From one side Amal supporters and from the other side supporters of the Future Movement were in the building facing mine. They started shooting at each other."

There were no reported deaths but as many as a dozen injuries.

Lebanon's sectarian and political tensions mirror a broader regional conflict. The U.S. and Saudi Arabia support the Sunni-led government while Iran and Syria back the Shiite-led opposition. Lebanon has been without a president since November amid a political deadlock between the two rival camps.

The latest upsurge of chaos in Lebanon's political crisis began when pro-government politicians accused Hezbollah of spying on the airport to prepare for attacks and assassinations as well as for establishing a private telecommunications system. The Cabinet decided to remove the airport chief.

Hezbollah warned the government against laying hands on the group's communications network, equating it to the weapons it stockpiles to take on Israel. The Shiite militant group's supporters said they would continue what in effect is a shutdown of the airport, a key transport conduit for a country that has hostile relations with one neighbor, Israel, and strained relations with another, Syria.