Libya appears to be on the brink of falling apart after a weekend of bloodshed in the capital that underlined the government's inability to rein in powerful militias who've become a law unto themselves in the anarchy triggered by the fall of dictator Moammar Gadhafi two years ago.

The persistent violence and the growing power of the unruly militias spawned by the 2011 civil war which run roughshod over the oil-rich North African state fractured between three regions -- Tripolitania in the west, Cyrenaica in the east and Fezzan which spans the Sahara desert in the south -- has reduced oil production, Libya's economic mainstay, to a virtual trickle.

A tense calm descended on Tripoli Sunday after more than 48 hours of bloodshed that began in the Gharghour district Friday when militiamen of the al-Nasour Brigade from the Misurata region east of the capital fired on protesters demanding the militias quit the city. But everyone seems braced for more trouble.

Officials said at least 47 people were killed and some 450 wounded after the militiamen opened fire with heavy weapons, reportedly including anti-aircraft guns, on the protesters.

Tripoli-based militias fired on the Misurata forces to aid the unarmed protesters, while militia chieftains in the city of Misurata, 120 miles east of the capital, moved more men and tanks toward the capital.

The al-Nasour Brigade took part in some of the heaviest fighting of the 8-month civil war in 2011 when Misurata was besieged by Gadhafi's forces.

NATO-backed rebel forces overthrew Gadhafi in August 2011, and he was later killed by an angry mob.

But since then the rebel alliance has collapsed and regional and tribal forces are pulling the country to pieces as they defy the shaky Western-backed government of Prime Minister Ali Zeidan and demand autonomy for the regions.

"A deteriorating security situation coupled with a corrupt and failed government is taking the country a step closer toward its second civil war," lamented Mustafa Fetouri, a Libyan analyst with the IHS Global Insight security consultancy in London.

While the elected General National Conference, Libya's parliament and top political authority, "remains paralyzed by infighting, corruption and a lack of leadership, the rogue, well-armed militias have effectively hijacked the country away from any real hopes and aspirations the Libyans might have after the collapse of the former regime," Fetouri observed.

"Today's Libya is divided because Libyans have yet to properly sit down together to settle their differences.

"Unless that happens, the call for federalism -- which is really a call for the division of the country -- will only become louder, and lawlessness will continue to be the norm."

Cyrenaica and Fezzan have already declared their autonomy within what they call a federal state.

Both are oil-producing regions, but Cyrenaica holds 60 percent of Libya's reserves of 47.1 billion barrels, the largest in Africa.

Armed groups and protesters have shut down much of the oil and gas industry since July.

That's reduced oil production from a post-revolution 1.4 million barrels a day, which oil workers had toiled prodigiously to restore after the civil war, to only 150,000-200,000 bpd.

Zeidan, who was kidnapped briefly by a militia on the defense ministry's payroll, said last week that 60 percent of Libya's energy facilities have been shut down, costing the state up to $130 million a day in lost revenue.

Ibrahim al-Jathran, a charismatic militia leader in Cyrenaica, has closed three of the region's four oil ports.

Earlier this month he formed his own militia-run oil company as part of the autonomous government his group declared in the ancient Roman province of eastern Libya, a direct challenge to Zeidan's government and the national oil company.

In a stunning act of irony, al-Jathran, an acclaimed rebel fighter who led the Hamza Brigade against Gadhafi's regime, was rewarded after the conflict with command of the Petroleum Security Guards who're supposed to guard energy facilities.

He's based in Benghazi, the eastern capital and longtime jihadist stronghold that was the crucible of the 2011 revolution against Gadhafi.

Now he's threatening to escalate his defiance of Zeidan by selling Cyrenaica's crude himself, cutting out what he says is a corrupt regime in Tripoli.

Zeidan can't afford to let that happen without watching the country disintegrate.