Yemeni President Ali Abdullah Saleh on Thursday condemned violence against protesters in Sanaa and directed the security authorities to bring the perpetrators to justice, the state-run Saba news agency reported.

Earlier the day, witnesses and medics said forces loyal to Saleh in the capital Sanaa opened fire to intercept a march of thousands of protesters demanding Saleh's prosecution, killing at least five demonstrators and wounding more than 25 others.

"The president condemned the violence against the protesters and directed the Interior Ministry to carry out an immediate investigation and bring perpetrators to justice," Saba quoted an official statement as saying.

Saleh, who was due to go to New York for medical check after signing a power-transfer deal initiated by the Gulf Cooperation Council (GCC) in Riyadh on Wednesday, said he hoped no more violence and urged all forces to exercise restraint, warning that "those who stand behind today's violence are seeking to drag the country into war."

Meanwhile, protesters at the Change Square in Sanaa said that "there is big conflict between the protesters and leaders of the opposition coalition after the latter agreed with Saleh and signed the GCC deal that granted immunity of the president."

"The protesters reject the GCC deal and vow to escalate their peaceful protests until their goals are meet, including an immediate end to Saleh's 33-year rule and putting him on trial," protest organizers said.

Under the GCC deal, the president would resign and hand over power to his deputy Abd-Rabbu Mansour Hadi in return for the immunity from prosecution.