More than 17 protestors and soldiers were killed in Yemen after government forces attacked an opposition camp in the capital Sanaa on Saturday night.
Hundreds fled from the midnight attack on the camp in Change Square the heart of an uprising where thousands have camped for eight months calling for President Abdullah Ali Saleh to quit power.
Protesters said the attacking forces included the elite Republican Guard and Central Security forces. Interior Minister Muttahar al-Masri however denied that a raid took place, blaming the gunfire on "extremists".
Saleh, who went to neighboring Saudi Arabia for medical treatment in June for wounds suffered in an assassination attempt, said on his return to Sana’a on Friday that he wants to end days of fighting and allow peace talks to take place.
Saleh's reappearance has raised questions over the future of Yemen, which has been rocked since January by protests against his 33-year rule.
Protesters moved forward in Sana’a this week by entering territory controlled by state forces, prompting a battle between loyalist and pro-opposition troops. About 100 protesters were killed in five days of bloodshed.