Protests have broken out across Syria as thousands heeded calls for a “day of defiance” against the regime.

Reports say that security forces killed five pro-democracy demonstrators and wounded dozens more in the city of Homs.

The protests began as Friday prayers ended. A march in Damascus did not last long before it was broken up. One opposition leader, Riad Seif, was arrested with other demonstrators, according to human rights campaigners.

Witnesses said security forces fired at protesters just north of the capital, wounding some.

The army, which stormed the southern city of Deraa last week, has deployed tanks in Homs and elsewhere.

New pictures show demonstrations in Aleppo in the north where students have previously taken to the streets.

The authorities blame what they call armed groups and say they have uncovered weapons. But witnesses and human rights campaigners accuse them of a relentless violent clampdown.

In the recent siege of Deraa it is alleged that the repression involved tanks, snipers, and mass arrests and beatings – including of the elderly, women and children.

Despite pledges by President Assad to reform, actions by the security forces indicate the exact opposite has been happening.