(Reuters) – At least 20 people were killed as Syrian tank forces battled opponents of President Bashar al-Assad in Homs on Monday, residents said, ahead of a planned visit by Arab League monitors to verify whether he is ending a violent crackdown on unrest.

A day before observers were to have their first look at the city at the heart of a nine-month-old revolt, there was no sign of Assad carrying out a plan agreed with the League to halt an offensive against protests and start talks with the opposition.

Amateur video posted to the internet by activists showed three tanks in the streets next to apartment blocks. One was firing its machinegun and another appeared to be firing mortar rounds. Gruesome video showed mangled bodies lying in pools of blood along a narrow street. Power lines had collapsed and cars were burnt and blasted, as if by mortar rounds.

An armed insurgency is increasingly eclipsing civilian protests. Now many fear Syria is sliding toward a sectarian war that pits the Sunni Muslim majority, the driving force of the protest movement, against minorities that have mostly stayed loyal to the government, particularly the Alawite sect to which Assad belongs. Fighting in Homs has intensified since a double suicide bombing in Damascus on Friday that killed 44 people.

“The Baba Amr (district) (of Homs) is being exposed to fierce shelling from heavy machinegun fire, armored vehicles and mortars,” the British-based Syrian Observatory for Human Right said in a statement.

“The violence is definitely two-sided,” said a Homs resident who named himself only as Mohammed to protect his safety. “I’ve been seeing ambulances filled with wounded soldiers passing by my window in the past days. They’re getting shot somehow.”

Parts of Homs are defended by the Free Syrian Army, made up of defectors from the regular armed forces, who say they have tried to establish no-go areas to protect civilians.

The Observatory documented names of those reported killed in Monday’s clashes sparked by a new wave of raids and arrests that also hit districts in Syria’s second city Aleppo. That business hub had been spared most of the upheaval until recently.

The initial 50 of 150 Arab League monitors were due to arrive in Syria on Monday, and some will go to Homs on Tuesday, a source at the group’s headquarters in Cairo told Reuters. Their job will be to assess whether Assad is withdrawing tanks and troops from Syria’s third largest city as promised.

“The element of surprise will be present,” said monitor Mohamed Salem al-Kaaby from the United Arab Emirates. “We will inform the Syrian side the areas we will visit on the same day so that there will be no room to direct monitors or change realities on the ground by either side.”

The mission’s objective is to confirm that the Syrian government is executing the Arab League initiative by withdrawing the military from cities, releasing prisoners and allowing Arab and allowing international media to visit.

Syria has barred most foreign journalists since the revolt began, making it hard to verify reports of events on the ground.

Other residents in Homs said they were running low on food as fighting left them trapped in their neighborhoods.

“We are hungry and cold. There’s no food, and we’re running out of fuel for heating,” said Tamir, an unemployed construction worker who hid with his family in their basement as heavy gunfire rocked the city.

Syrian state television has regularly shown some areas of Homs, a city of one million, looking peaceful. But activist video on the internet shows other areas looking like a war zone of empty streets, crumpled bodies and blasted buildings.

SPLIT IN SYRIAN NATIONAL COUNCIL?

The Syrian state news agency SANA reported clashes further south on Monday. “Civilians and forces to preserve security have been exposed to attacks by armed terrorist groups in the village of al-Lijat in Deraa province,” it said.

SANA said “a number” of the group were killed. One soldier died and eight were wounded. The agency also said Syrian forces disabled four improvised explosive devices on main roads close to the flashpoint city’s main fuel station.

A source inside the opposition Syrian National Council said a growing number of its members are pushing to openly endorse armed insurrection against the government. But they faced resistance from those dealing diplomatically with Western powers and calling for U.N. support or foreign intervention in Syria.

The United Nations says at least 5,000 Syrians have been killed the revolt, inspired by other Arab uprisings this year that have toppled three dictators, broke out in March – and an estimated one-third of deaths have occurred in and around Homs.

The Syrian authorities blame the violence on foreign-backed armed Islamists who they say have killed 2,000 members of the security forces. After six weeks of stalling, Damascus signed a protocol this month to admit the Arab League monitors.

Assad, 46, succeeded his father in 2000 to carry on a dynasty that has ruled for 41 years. He has responded to popular calls to step down with a mixture of force and promises of reform, announcing an end to a state of emergency and promising a parliamentary election in February.

The first group of about 50 Arab League monitors, led by Sudanese General Mustafa Dabi, will be divided into five 10-man teams going to five locations.

“We’re waiting. Let’s see,” said Homs resident Mohammed. “We hope they work the way they should. We hope they will be neutral … If they are neutral they will be condemning everyone but most especially the (Syrian) authorities because they are the ones who should be responsible for protecting people.”

Arab League mission chief Dabi reached Damascus on Saturday while the capital was still reeling from suicide bombings the day before that marked an ominous escalation of the violence.

Assad’s opponents say they suspect his government carried out the Damascus bombings itself to prove to the world that Syria is facing indiscriminate violence by armed Islamists and to intimidate the work of monitors.

“The Assad regime, through the two suicide attacks in Damascus on Friday, has given the Syrian people and Arab states two choices: Either it remains in power or it will confront them with killing and terrorism,” said Paris-based Syrian National Council president Burhan Ghalioun.

“The explosions in Damascus carried the signature of the Syrian intelligence forces,” he told Asharq Alawsat newspaper. “But these terrorist operations will not discourage people from continuing the revolution to topple this regime no matter the sacrifices. It is no longer acceptable to blackmail us through terrorism.”

Reuters