Washington: Iran is sending trainers and advisers to Syria to help crush anti-government demonstrations threatening to topple Iran's most important ally in the region, The Washington Post reported late  onFriday.

The influx of Iranian manpower was adding to a steady stream of aid from Tehran, the newspaper said, citing unnamed US officials. That aid includes not only weapons and riot gear but also sophisticated surveillance equipment that is helping Syrian authorities track down opponents through their Facebook and Twitter accounts, the sources said.

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Iranian-assisted computer surveillance is believed to have led to the arrests of hundreds of Syrians seized from their homes in recent weeks, the paper said.

According to one diplomat and US officials, the Iranian military trainers are being brought to Damascus to instruct Syrians in techniques Iran used against the nation's "Green Movement"' in 2009, the Post reported.

Officers from Iran's notorious Quds Force have played a key role in Syria's crackdown since at least mid-April, it said. US sanctions imposed against the Quds Force in April had been intended as a warning to Iran to halt the practice, said the Post.

At least eight people were reported killed by security forces Friday as pro-democracy protesters took to the streets in cities and towns across the country after Muslim Friday prayers in defiance of a government crackdown.

The death toll by early evening was far lower than last Friday when at least 44 people were killed by security forces during similar protests. Since the revolt in Syria erupted in mid-March, Friday protests have become a weekly ritual and are widely seen as a barometer of whether activists are able to maintain momentum despite the repression.