The death toll from an attack by Syrian forces in the northern province of Idlib on Tuesday has risen to at least 56, the opposition Syrian Observatory for Human Rights said on Wednesday.
The British-based group said it had documented the names of 56 "citizens and wanted activists" who were killed, but that dozens more may have died. The Observatory's Rami Abdulrahman said one activist in the area reported 121 bodies had been taken to local hospitals.
Events in Syria are difficult to verify because the government has banned most independent reporting.
The latest violence comes ahead of an Arab League monitoring mission to verify Syria's implementation of a plan to end the bloodshed. The first officials are due Damascus on Thursday and monitors should arrive by the end of the month, the League says.
At least 5,000 people have been killed in President Bashar Assad's crackdown on protests which erupted in March, according to the United Nations human rights chief.
Syria says it is fighting foreign-backed armed groups who have killed more than 1,100 security force members.
The news of the deaths comes in the wake of reports which revealed that more than 10,000 soldiers have deserted the Syrian army, with as many as half the conscripts not reporting in the last three call-ups.
According to Western intelligence agencies, even though the top brass is still loyal to Assad, lower-level officers are deserting in large numbers, and in some cases, whole units have deserted en masse.
The army is considered the main factor safeguarding Assad's regime, after mass protests began in the south in March and spread throughout the country, inspired by the demonstrations elsewhere in the Arab world.
On Tuesday, at least 73 people were killed in Syria in clashes between the army and opposition, most of them in Homs in the west and Idlib in the northwest. The 73 dead added to the 100 who were killed on Monday, among them 14 soldiers ambushed by opposition forces, human rights groups said.
The groups added that Assad's forces were transferring wounded opposition activists from hospitals to army bases to prevent them from testifying to Arab League observers expected to arrive under a deal struck on Monday.
The observers would ensure that the army and opposition adhere to a cease-fire and end the violence.
A new law imposes the death penalty on anyone "smuggling arms to be used in terrorist activity."
Israeli Defense Minister Ehud Barak predicted this month that the Syrian regime would collapse within weeks. Barak said it was impossible to know who would rule Syria in the future, but in any case it would be a blow to the alliance between Iran and Lebanese Shi'ite group Hezbollah.
Another sign of the Syrian regime's frailty is Hamas' decision to move its headquarters from Damascus, as the Palestinian group that runs the Gaza Strip prepares for a possible post-Assad era.
More than 5,000 people have been killed in the unrest in Syria, most of them anti-Assad activists; in recent days dozens have been killed every day, on average. Still, the army has suffered many losses, mainly from ambushes by opposition forces and ex-soldiers. In some remote districts the opposition groups are getting stronger and the army is having problems operating.
The opposition is still weak in the two large cities, Damascus in the south and Aleppo in the north. The Syrian Republican Guard, concentrated mostly in Damascus, is well armed and considered loyal to Assad, making it more difficult to organize demonstrations in the capital.
Still, even in Damascus, rockets have been launched at army vehicles.
One of the main worries in the West is the fate of the army's rocket and missiles caches, as well as its chemical weapons. According to several media reports, Hezbollah has transferred several long-range missiles from Syria to Lebanon.
In the 2006 Second Lebanon War, Hezbollah fired more than 4,000 rockets into Israel.
At this stage there is no proof that Hezbollah has transferred chemical weapons. Chemical weapons are not easy to maintain and handle, and as far as is known, Hezbollah does not have such expertise.
Israeli Military Intelligence recently presented the government with a report stating that unrest in Arab states will continue into next year. Military Intelligence says the unrest might topple the regimes in Syria and Yemen; in Yemen, outgoing President Ali Abdullah Saleh still has not relinquished all his powers despite the uprising in that Arabian Peninsula country.
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