Amman // Regime forces have launched some of their most intensive attacks in southern Syria since the uprising started there more than three years ago, according to rebel commanders, in what appears to be a concerted push by forces loyal to president Bashar Al Assad to retake lost ground.

After forcing rebels out of Homs, Syria’s third-largest city, earlier this month, regime units now seem to have refocused on the strategically important southern front, near the border with Jordan and Israel.

Rebels say attacks since Friday in the towns of Nawa, Inkhil, Jasem and Deraa city, where the revolt began peacefully in March 2011, are among the heaviest they have suffered. Some field commanders described them as the worst they have seen in more than two years of often heavy combat.

There are no reliable casualty figure at present, opposition sources said, because of the chaotic situation on the ground.

On Sunday, the regime’s air defence chief was reported killed in fighting near Damascus. Although not announced officially, rebels and activists said Lt Gen Hussein Ishaq died on Saturday in an attack on an air base near the town of Mleiha.

Meanwhile, rebels in the south say the regime has used surface-to-surface missiles, air strikes, artillery and barrel bombings in its renewed assault in Deraa, with tanks advancing around Nawa and Tal Al Jabiyeh, hilltops near the frontier with Israel where rebels have been making small gains in recent months.

Sana, the state-run news agency, said “wide military operations” were under way in Deraa on Sunday.

“Army units destroyed terrorists’ vehicles, weapons and ammunition in Deraa and its countryside,” Sana reported, using regime terminology for rebel groups.

Iran’s Fars news agency also reported that regime forces had retaken the headquarters of Battalion 74 in Deraa province, which had been rebel-held.

Despite the assaults, rebel supply lines were holding up on Sunday, according to Free Syrian Army (FSA) officers, who said they were managing to stand their ground.

“We have the situation under control. The regime is trying to take Tal Al Jabiyeh and Nawa, it has reinforced its positions and sent in tanks with air support but we have thwarted the attacks and several tanks have been destroyed,” said a rebel officer.

However, another FSA commander overseeing operations around Nawa made a plea for reinforcements, saying FSA units there were facing regime troops backed up by Iranian Revolutionary Guard units, and needed help.

“Several FSA groups made small [diversionary] operations outside of Nawa and made videos of themselves fighting but then they left, and didn’t share their ammunition or weapons with us,” he said, criticising them for not staying to aid their embattled colleagues.

“The regime is taking its time bombing Nawa and is prepared to keep bombing it until nothing is left. We are facing a real war,” he said.

Guerrillas from Hizbollah, the Lebanese Shiite militia, have also been reported in the area, according to a rebel commander with contacts inside the Military Operations Command in Amman, the secretive operations room staffed by western and Arab intelligence that supports rebels in the south.

He said rebel intelligence assessments indicated several hundred Hizbollah fighters had recently been deployed to the south.

Iran and Hizbollah, together with Russia, have played a major role in supporting the Assad regime, providing manpower, military expertise and weapons that have enabled government forces, weakened by defections and mistrust, to hold off the rebels and, since last summer, to retake what had been rebel-held areas such as Qusayr and Homs.

On the other hand, backing for the rebels from western and Arabian Gulf states has been more equivocal.

The timing of the latest Deraa attacks could hardly have been more critical for rebel forces. A united rebel front in the south has collapsed in the past two weeks, with a dangerous rift opening between the FSA and Jabhat Al Nusra.

Cooperation between the two factions halted after the Al ­Qaeda-affiliated group captured and tortured an FSA commander, Col Ahmed Nehmeh. He remains in their custody despite negotiations to secure his release.

While the rebel infighting that has ravaged the northern and eastern fronts has not yet broken out in the south, the suspension of a fruitful working relationship between the increasingly powerful Al Nusra and the FSA will harm their ability to withstand the regime assault, opposition commanders and activists said.

In contrast to the stalemate on the northern front, Syria’s southern front has been relatively successful for the rebels, who launched an offensive of their own in February. Their gains have not been dramatic, but they have nonetheless inched forward, taking checkpoints and pushing out regime forces along the border with Israel.

Lt Col Nijem Abu Al Majd, a Deraa-based FSA commander, said he believed the latest assault was a panicked response by Damascus to the steady rebel gains.

“We are liberating more areas, especially in the west of Deraa. The regime was shaken, and because it is unable to reclaim liberated areas especially due to the lack of sufficient manpower, therefore, it has resorted to the excessive use of force,” he said.

The southern front may represent the opposition’s best hope of getting to Damascus, 90km north of Deraa, avoiding regime strongholds in central and western Syria. However rebels in the south have been unable to cut off regime supply lines, or link up decisively with rebels on the southern and eastern outskirts of Damascus.

Another FSA colonel said the latest regime offensive was an attempt by Mr Al Assad to “polish his image ahead of the presidential election next month”.

“The regime wants to show it is powerful, so it is bombing us more heavily than before,” he said.

The much-criticised presidential election, in which Mr Al Assad will face token, regime-approved opponents for the first time in a ballot, is due to take place on June 3.

Voting will only take place in regime-held areas, not the approximately 40 per cent of the country outside of its control.

Hundreds of thousands of refugees have been denied votes by the regime, the opposition is boycotting the ballot and the UN has criticised it as a contravention of the Geneva peace plan to end the conflict in which more than 150,000 people have been killed.

Since it began in March 2011, the peaceful uprising-turned-proxy-war has dragged in regional and world powers, laid waste to densely populated areas and seen a meteoric rise of extremist factions in Syria; Al Qaeda on the rebel side and Shiite militias with the Assad regime.

psands@thenational.ae