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Syrian forces shell towns, clash with rebels

A civil war is breaking out in Syria between the Sunnis and Shiites with militia groups fighting along sectarian lines. Sources report regular gun battles close to the presidential palace where the Syrian regime is experiencing problems controlling its own armed forces. NBC's Richard Engel reports.

Syrian forces shelled opposition strongholds in the central province of Homs and eastern Deir al-Zor on Monday and clashed with rebels in violence that killed 29 people across the country, the Syrian Observatory for Human Rights said.

Activists said Syrian troops attacked a rebel-held town with helicopter gunships and shelled other restive areas across the nation. The aerial assault targeted the strategic river crossing town of Rastan, which has resisted repeated government offensives for months, the activists said. 

"The regime is now using helicopters more after its ground troops suffered major losses," said Rami Abdul-Rahman of the Britain-based anti-government group Syrian Observatory for Human Rights, which uses a network of sources on the ground. "Dozens of (military) vehicles have been destroyed or damaged" since the end of May, he said. 

'Battle is in Damascus' as Syrian tanks fire in 12-hour exchange

Undeterred by international condemnation, the Syrian military continued its unrelenting shelling of the city of Homs. NBC's Ayman Mohyeldin reports.

Syrian Foreign Ministry spokesman Jihad Makdissi recently said that rebels are now using sophisticated anti-tank missiles. Videos posted by activists over the past week have shown many destroyed tanks and armored personnel carriers. 

According to videos posted online, fireballs of orange flame and black rubble exploded in the air as waves of shells pounded residential buildings in Homs on Monday. The sounds of shells whooshed through the sky and there was occasional sporadic machine gun fire. 

The videos could not be independently verified. 

Annan: 'Gravely concerned'
Also on Monday, international envoy Kofi Annan said he was "gravely concerned" about the latest violence in the country, citing shelling of opposition areas of Homs and reports of mortar, helicopter and tank attacks near the coast. 

Reporter: Syrian rebels set us up to be shot at by Assad's army

In a statement, Annan said there was an escalation of fighting by government and opposition forces. Violence has spiked in recent weeks, with both sides ignoring a U.N.-brokered cease-fire that was supposed to go into effect on April 12 but never took hold. 

Annan demanded both sides "take all steps to ensure that civilians are not harmed." 

In Damascus, the state-run news agency SANA said authorities foiled an attempt to blow up a car rigged with 1,500 pounds of explosives in the Damascus suburb of Chebaa. Experts dismantled it Monday, SANA said. 

The Dylan Ratigan Show Mega Panel of Karen Finney, Susan Del Percio, and Jimmy Williams discuss the ongoing crisis in Syria, where on Thursday alone 80 people died and 18 homes were either destroyed in the shelling or burned down. The Mega Panel goes on to cover New York's evolving relationships with larger sugary drinks and marijuana.

Syrian activists say 13,000 people have been killed in violence since the uprising began in March 2011. According to U.N. figures, soldiers and militias loyal to President Bashar Assad have killed at least 10,000 people.

Smell of death at the scene of massacre in Syrian village, UN monitors say

The bloodshed has led to broad condemnation of the regime from the international community, although Russia, Iran and China have stood by Assad. Russia and China have vetoed two Security Council resolutions that threatened sanctions against Syria. 

Russia has refused to support any move that could lead to foreign intervention in Syria, Moscow's last significant ally in the Middle East. 

Russian Foreign Minister Sergey Lavrov is scheduled to visit Syria's ally Iran on Wednesday.

The Associated Press and Reuters contributed this this report.

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