Medical officials in Yemen say security forces have fired on protesters in the capital Sanaa, killing eight and wounding at least 38.

The officials said the security forces opened fire with live ammunition on Saturday when tens of thousands of protesters approached an area of central Sanaa under the control of the Republican Guards, an elite force led by the son of embattled President Ali Abdullah Saleh. They also used tear gas and water hoses to disperse the protesters.

The officials spoke on condition of anonymity because they were not authorized to speak to the media.

Saturday's demonstration was part of an eight-month-old protest movement calling for the ouster of Saleh, Yemen's leader of 33 years.