Tanks shelled a Syrian border town for the fourth day on Wednesday in a military campaign to crush demonstrations against President Bashar al-Assad, under mounting Western pressure to stop his violent repression of protesters.

Troops went into Tel Kelakh on Saturday, a day after a demonstration there demanded "the overthrow of the regime", the slogan of revolutions that toppled Arab leaders in Egypt and Tunisia and challenged others across the Middle East.

Assad had been partly rehabilitated in the West over the last three years but the United States and European Union condemned his use of force to quell unrest and warned they plan further steps after imposing sanctions on top Syrian officials.

The Syrian leader told a delegation from the Damascus district of Midan that security forces made mistakes handling the protests, Wednesday's edition of al Watan newspaper said.

One delegate said Assad told them 4,000 police would receive training "to prevent these excesses" being repeated, it said.

Human rights groups say Assad's crackdown has killed at least 700 civilians. Authorities blame most of the violence on armed groups backed by Islamists and outside powers, saying they have also killed more than 120 soldiers and police.

"We're still without water, electricity or communications," a resident of Tel Kelakh said, speaking by satellite phone.

He said the army was storming houses and making arrests, but withdrawing from neighbourhoods after the raids. In a sign that the army was coming under fire in the town, he said some families "are resisting, preferring death to humiliation".

Syria has barred most international media organisations from operating in Syria, making it hard to verify reports from activists and officials.

Prominent human rights lawyer Razan Zaitouna said the army and security forces have killed at least 27 civilians since the army moved into Tel Kelakh.

The state news agency SANA quoted a military source saying eight soldiers had been killed on Tuesday in Tel Kelakh and in the southern rural Daraa province where protests first broke out exactly two months ago.

It said five of the dead were killed when an "armed terrorist group" fired on a security forces patrol near Tel Kelakh, which is close to Lebanon's northern border.

The Tel Kelakh resident said artillery and heavy machinegun fire hit the main road leading to Lebanon overnight, as well as the Abraj neighbourhood inhabited by minority Turkmen and Kurds.

"Most residents of Tel Kelakh have fled. Some remaining people tried to escape to Lebanon yesterday but the shelling has been too heavy," the resident said.

"Abraj residents have issued a call to (Turkish Prime Minister Tayyip) Erdogan to help them. But it is like the drowning hanging on to a straw," he said.

Erdogan said last week 1,000 people have been killed in Syria's unrest, and has become increasingly critical of Assad.

TANKS MOVE INTO SOUTHERN CITY

U.S. Secretary of State Hillary Clinton said on Tuesday Washington would respond to Syria's crackdown with additional steps in coming days if the government does not change course.

Syrian tanks also moved into a southern city on the Hauran Plain on Tuesday after encircling it for three weeks. Soldiers fired machineguns as tanks and armoured personnel carriers entered Nawa, a city of 80,000 people 60 km (40 miles) north of the city of Daraa, according to activists from the region.

"The governor (of the province) had announced that the troops have the names of 180 wanted men in Nawa, but the arrests are arbitrary," one rights campaigner said.

In a possible indication of the ferocity of the crackdown, villagers near Daraa have found two separate graves containing up to 26 bodies, residents said on Tuesday. Syrian authorities dismissed such reports as part of "campaign of incitement".

Daraa residents said tanks were still on the streets of their city and rights campaigners said the southern towns of Inkhil and Jassem also remained besieged.

Mass arrests continued in the Hauran Plain and other regions of Syria, they added.

Protests erupted in the Damascus suburb of Douma, Syria's second city Aleppo, the town of Zabadani in the foothills of mountains separating Syria and Lebanon, the central town of Rastan, Hama and the Deir al-Zor region near Iraq's border.

Most were not large but rights campaigners said they were significant given the severe security clampdown.