Syria's president said the country's security forces have made mistakes during the uprising against his regime, blaming poorly trained police officers at least in part for a crackdown that has killed more than 850 people over the past two months.

President Bashar Assad's comments, carried Wednesday in the private Al-Watan newspaper, came even as a human rights activist said Wednesday that Syrian troops have used heavy machine guns to attack a neighborhood in the central city of Homs.

Still, his remarks were a rare acknowledgment of shortcomings within Syria's powerful security agencies. Assad said thousands of police officers were receiving new training.

The brutal crackdown across Syria has sparked international condemnation, and the United States and European Union are planning new sanctions against the Syrian leadership. More than 850 people have been killed in the crackdown on protests that erupted in mid-March, according to Syria's top rights organization.

The Swiss government on Wednesday passed a measure restricting arms sales to Syria and freezing the assets and banning the travel to Switzerland of 13 senior Syrian officials. The arms embargo is largely theoretical because Switzerland hasn't exported weapons to Syria in over a decade, but any Swiss banks holding assets of the 13 officials will have to declare them immediately to the government.

But Assad got a boost from an old ally Wednesday, with Russian President Dmitry Medvedev saying Moscow will not support any United Nations resolutions that would open the way for interference in Syria's internal affairs.

Medvedev said Assad must be given a chance to fulfill his reform promises and warned against foreign interference in the country.

The Syrian opposition called for a general strike Wednesday to protest the regime but the appeal seemed to go largely unheeded. Schools, shops and other businesses were open in the capital, Damascus, and other Syrian cities amid a tight security presence.

The call for a strike was an attempt by opposition forces to hit at Assad's regime from new angles: its economic underpinnings and ability to keep the country running during two months of widening battles.

But the fact that it apparently fell flat suggests that Assad still has support in the business community and that a sweeping campaign of intimidation was working.

"Everything is open," said a resident of the central city of Homs, which has seen daily anti-government protests in the past weeks. He said residents would not dare comply with the strike in light of the heavy security presence in the city.

The latest place to witness a harsh crackdown has been the western town of Talkalakh, where 27 people have been killed since last week, according to activists.

Syrians fleeing to Lebanon in recent days have described horrific scenes of execution-style slayings and bodies in the streets in Talkalakh, which has been reportedly encircled by security forces.

More than 5,000 people have crossed from Talkalakh across a shallow river into Wadi Khaled on the Lebanese side of the border. The flow, however, appeared to be slowing Wednesday, with very few people seen crossing into Lebanon.

Assad "is not a president," said Mohammad, a Syrian who fled Talkalakh three days earlier and was taking shelter along with others in a mosque in Wadi Khaled. "We elected him to protect us and shelter us, not to displace us," he told Associated Press Television News.

At least one family of women was seen returning to Syria with bread and other groceries they had bought in Lebanon.