YEMEN. Pressure on Ali Abdullah Saleh to resign intensified on Saturday when the leaders of two of Yemen's most important tribes abandoned the president and joined the anti-regime movement.
The news came as an official denied reports that police killed four people on Friday in an assault on an anti-government protest in Aden, blaming a southern secessionist group for the attack.
Powerful tribal leaders, including those of the Hashid and Baqil, pledged to join protests against Saleh at a gathering north of the capital, a tribal source told AFP.
"I have announced my resignation from the General People's Congress in protest at the repression of peaceful demonstrators in Sanaa, Taez and Aden," Hashid tribal chief Sheikh Hussein bin Abdullah al-Ahmar was quoted as saying, in reference to the ruling party.
The Hashids are considered Yemen's most powerful tribal confederation and include nine clans, among them the Sanhan, long a bulwark of Saleh's regime.
The announcement was warmly received by a large crowd of tribesmen, including members of Yemen's second largest tribe, the Baqil, who gathered for the meeting, according to the tribal source.
The two tribes announced they would support the popular uprising against Saleh, who has refused to step down after three decades in power, to chants of "the people want the fall of the regime!"
According to an AFP tally based on reports by medics and witnesses, at least 19 people have now been killed in almost daily clashes at anti-regime protests since they erupted on February 16.
Medics said security forces used live ammunition on a demonstration in the southern city of Aden, which has seen the worst violence, bringing the death toll to four on Saturday from just one rally with 40 others wounded.
They identified three of the dead as demonstrator Mohammed Ahmed Saleh, 17; Hael Walid, 21, and Salem Bashaj, an employee at the state electricity company who was shot outside his home.
A hospital official in Aden told AFP that a fourth protester died of wounds sustained in the gunfire, which came after Saleh said he had ordered his forces to protect both pro- and anti-government demonstrators.
Residents of Aden described the Friday night incident as a scene from the frontlines of all-out war.
"Our neighbourhood has witnessed real scenes of war waged by forces of the Republican Guard, who have been targeting our innocent young who want to protest peacefully," one resident told AFP.
News of 17-year-old Saleh's death sparked a wave of anger in neighbourhoods across Aden, where residents attacked police stations and set fire to a police car, an AFP correspondent said
Aden remained tense on Saturday, an AFP correspondent said, as a handful of families searched for missing relatives whom they believed were arrested.
A Yemeni official, however, denied reports of a police raid.
"An armed separatist group loyal to the so-called Hirak (Southern Movement) randomly opened fire with automatic weaponry on buildings in the district of Maalla, targeting security forces and citizens," the defence ministry's 26sep.net website quoted the security official as saying.
President Saleh has stubbornly refused to resign, but said he will not seek re-election in 2013 and promised political reforms.
A Friday demonstration, dubbed "the beginning of the end" of Saleh's regime which swept to power in 1978, saw 100,000 Yemenis turn out across the country, organisers said.
Pro- and anti-government demonstrators have also clashed in recent days, with Saleh loyalists locking horns with militants from the Southern Movement in the country's south.