Syrian tanks have rumbled into a rebel bastion in Damascus under the
cover of heavy tank and gunfire, activists said, as UN observers toured
hotspots in the country.
Activists say the Sunday morning raid
was launched to crush president Bashar al-Assad's opponents in Douma,
an outlying suburb of the captial.
A video posted online showed columns of smoke billowing into the sky. Heavy gunfire could be heard in the background.
"Regime
forces enter Douma each day, but today's assault was the largest,"
Damascus revolutionary council member Mohammed Saeed told AFP.
He
said it was "in retaliation for huge anti-regime protests there and
because it's a centre of dissent in the Damascus countryside".
The Syrian Observatory for Human Rights two civilians and four soldiers were killed in Douma.
The violence comes a day after the UN Security Council voted unanimously to dispatch 300 unarmed observers to Syria to monitor a ceasefire that went into effect on April 12.
UN envoy Kofi Annan has called the vote a "pivotal moment for the stabilisation of the country".
An advance team of UN observers toured embattled areas on Sunday, laying the ground for the new mission.
On
Saturday, their visit to Homs included a stop in Baba Amr, a rebel
hideout battered by a month-long army bombardment that killed hundreds,
according to monitors, before it was retaken on March 1.
A YouTube video showed them meeting with activists who begged them to stay.
"Today
is the first day since two months, exactly since 5 February... in Homs
without shelling... without killing, without fire," one unidentified
activist said in the footage.
"Because of that, we want you to stay. Please stay. This is what we want.
"When
you come, shelling stops. When you come, killing stops," he told the
observers, who wore blue helmets and bullet-proof vests marked UN.
Two monitors later set up base in Homs to ensure the end of months of bloodshed.
Meanwhile Mr Annan made a fresh appeal for both sides of the violence to put down their weapons.
"I
urge all forces whether governmental, opposition or others to put down
their weapons and work with the United Nations monitors to consolidate
the fragile cessation of violence," he said in a statement.
"The
government in particular must desist from the use of heavy weapons and,
as it has committed, withdraw such weapons and armed units from
population centres and implement fully its commitments under the
six-point plan."
The Observatory also reported bloodshed outside of Douma on Sunday.
Soldiers
shot dead three civilians at Rami village, in Jabal al-Zawiya district
of north-western Idlib province, the Observatory said.
In Banias,
meanwhile, the group said an overnight ambush on a patrol killed one
security forces member and wounded three others, the first such
incident in the northern coastal city for nearly a year.
The reports could not be independently verified.
The UN says well over 9,000 Syrians have been killed since democracy protests erupted in March 2011.