SANAA, Yemen (AP) - President Ali Abdullah Saleh abruptly returned home to Yemen on Friday after more than three months of being treated in Saudi Arabia for wounds from an assassination attempt, in a move apparently aimed to ensure his grip as his loyalists and opponents wage urban warfare in the capital.
Hours after his return, fighting intensified as government forces in armored vehicles closed in on the thousands of opposition activists in the capital's main protest camp, which had already been under heavy bombardment by mortar shells throughout the day. The bloodshed reinforced fears that Saleh's return signaled an escalation of fighting into a full-fledged attempt to crush his rivals.
The White House was blindsided by the sudden return. U.S. officials conceded it was a surprise and said Secretary of State Hillary Rodham Clinton wasn't warned of Saleh's plans when she met Tuesday in New York with the foreign minister of Saudi Arabia, which has been working with Washington and Yemen to try to arrange a transfer of power.
The return could be a significant blow to those attempts. A degree of stability in the strategic but impoverished Arab nation is a priority for the United States, which wants a partner to continue the fight against one of al-Qaida's most active branches, based in Yemen and accused of plotting attacks in the U.S. Islamic militants have already exploited months of turmoil to seize control of cities in southern Yemen.
Abdullah Obal, an opposition leader, said he believed Saleh "returned to run the war and drive the country into an all-out civil war."
"The cannons are now speaking. Gunfire is doing all the talking," Obal said.
After midnight, forces from the Central Security Police, including some in armored vehicles, moved in on neighborhoods around the capital's main protest camp, known as Change Square. Thousands of protesters have held a sit-in there since the start of their movement in February.
The police waged gunbattles with an army unit that defected months ago and is guarding the protesters at the square, witnesses said. At the same time, government forces continued to lob mortar shells into the square, setting several activists' tents on fire, said protester Walid Rafei.
Throughout the day, three people were killed there, according to medic Mohammed al-Qabati.
Saleh made no immediate public appearances, but his return breathed life into the camp of his supporters who turned up in the thousands for the Friday sermon that became a massive show of faith in the country's leader for 33 years.
"We love you, Ali," chanted thousands massed on Boulevard 70, a street near the presidential compound.
The return threatens to further break open the deep divisions that have riven Yemen since the protest movement kicked off in February demanding Saleh's ouster and an end to his authoritarian regime. Saleh's security forces cracked down hard on protesters, killing hundreds, which prompted members of his government, military and allied tribes to join the opposition.
In early June, an explosion ripped through a mosque where Saleh was praying in his Sanaa presidential compound. The blast left him severely burned over much of his body and wounded with wooden shards, and nearly a dozen of his top aides were seriously wounded. Saleh has since been in Saudi Arabia for treatment.
Both the U.S. and Saudi Arabia were believed to be trying to keep Saleh from leaving Saudi Arabia, and signing onto a deal proposed by Gulf Arab states, under which he would resign and hand power to his vice president to form a national unity government in return for immunity from any prosecution.
The mercurial Saleh has repeatedly promised to sign the agreement, then refused at the last minute.
White House Press Secretary Jay Carney said Friday, "We urge President Saleh to initiate a full transfer of power and arrange for presidential elections to be held before the end of the year within the framework" of the agreement.
"A political solution is the best way to avoid bloodshed," he said.
This week, the deadlock that endured even during Saleh's absence broke down into the worst violence in months after he recently delegated his vice president to restart negotiations with opponents on the deal. It was considered another stalling tactic by Saleh. It sparked an escalation in the protests and a violent crackdown in Sanaa and other cities.
Forces loyal to the president's son Ahmed attacked protesters in the streets and battled troops led by one of the regime's top rivals, Maj. Gen. Ali Mohsen al-Ahmar, a former Saleh aide who joined the opposition early in the uprising, as well as tribal fighters who back the protesters.
Around 100 people have been killed - mostly protesters as regime troops hit their gathering with shelling or barrages of sniper fire from rooftops. Residents have been forced to hunker down in their homes or flee the city as the two sides exchanged bombardment over Sanaa from strongholds in the surrounding hills.
Saleh slipped back into the country before dawn on Friday. In a statement on the state news agency, he called for a truce, saying "the solution won't be through cannons and barrels, but through dialogue, understanding and ending the bloodshed."
But his opponents dismissed the negotiations call, convinced that Saleh has no intention to step down and aims to break his rivals with military force. Sultan al-Barkani, the head of the ruling party's bloc in parliament and a Saleh backer, told Al-Jazeera television that it was "totally unlikely" the president will resign. "Saleh will not leave except through elections," he said.
Obal, the opposition member, blamed the U.S. and Saudi Arabia for not exerting enough pressure on Saleh to quit. He said the opposition was hardening its position in the face of Saleh's return and that any accord "can no longer give guarantees against prosecution amid all this killing."
In other violence Friday, mortar shells hit a group of anti-Saleh tribal fighters in a neighborhood where battles have raged with Saleh loyalists, killing two tribesmen.
During a brief lull in the fighting, there were mass protests by both sides.
At the opposition rally on Boulevard 60, demonstrators carried pictures of those killed in the violence as speakers urged security forces to stop killing their own people. "The people want the trial of the butcher," the crowd chanted.
Abdel-Hadi al-Azazi, a protest leader, warned that Saleh's return means "more divisions, more escalation and confrontations."
"We are on the verge of a very critical escalation," he told the Associated Press.
April Alley, a Yemen researcher with the International Crisis Group, said Saleh's surprise return put both his supporters and opponents off balance, creating an explosive situation but one with also high stakes.
"There is greater incentive to actually come through with a deal," she said, particularly as negotiations over ways to implement the power transfer had been ongoing until the recent violence.
Retired army general Ahmed Salem said Saleh, an astute military man who has balanced tribal and security loyalties for decades, will be driven by the battle cry.
"He will attempt to stop the advances of his adversaries, and will try to improve his situation on the ground," Salem said. "His return will enable his supporters, lifts their spirit after a period of confusion because of lack of political management."