(CNN) -- Dozens of suspected al Qaeda militants escaped Wednesday from a jail in the Yemeni city of Mukalla, a senior security official said.
An Interior Ministry official said 63 members of al Qaeda had managed to break out of Almakla prison, according to the state-run SABA news agency. He said three were killed and another two arrested and that a prison guard was killed. He asked to remain anonymous because he is not authorized to speak to the media.
Some of the escapees had already been convicted; others were awaiting trial, the official told SABA. They escaped by digging a 35-meter (115-foot) tunnel, he said.
Witnesses said armed militants began attacking the prison at about 8 a.m. and fired heavy artillery before the escape.
The prison break comes two days before Yemeni President Ali Abdullah Saleh, who is being treated in Saudi Arabia after an attack on his compound, is to return to Yemen, his party said Tuesday. Opposition leaders called the news of Saleh's planned return a false rumor.
Saleh and other senior officials were wounded June 3 in an attack on the mosque at the presidential palace and taken to Saudi Arabia for treatment.
Yemen has been consumed by unrest for months as protesters have demanded an end to Saleh's rule. In recent weeks, government troops have battled both anti-government tribal forces and Islamic militants, including al Qaeda in the Arabian Peninsula.
But in recent days, the Yemeni government's control has been receding, said Christopher Boucek, an associate in the Middle East program at the Carnegie Endowmen for International Peace. "There are instances where you can say that the Yemeni government is instigating some of this chaos -- with the goal to demonstrate to the United States, Saudi Arabia and others that this regime -- the government of President Saleh -- is the best to fight al Qaeda."
Boucek said the Yemeni government is more concerned with protecting itself from the popular revolt than with going after al Qaeda. As a result, he said, the government has repositioned its counter-terrorism forces, retreating from areas such as Abyan province where it had lost ground and circling the wagons.
However, a Yemeni official briefed on security operations rejected Boucek's conclusion. "What about the blood of 66 soldiers?" he said, citing the number of soldiers who he said have died in Abyan province alone in recent weeks. Another 291 soldiers have been wounded in operations there that killed six of the most wanted al Qaeda operatives and 40 other militants, he said.
The official said it was not clear how Wednesday's prison break occurred. But, he said, the area was "shut down," military and police forces were on high alert, and forces were looking for the escapees.
Recent clashes in the southern province of Abyan killed seven Yemeni soldiers and 17 militants. The fighting was mainly concentrated in the cities of Zinjibar and Jaar.
Government troops have been battling both anti-government tribal forces and Islamic militants, including al Qaeda in the Arabian Peninsula.
The United States has been aiding Yemen's military in its fight against Islamic militants amid fears that al Qaeda is exploiting the political chaos and leadership vacuum engulfing the unstable and impoverished Arabian Peninsula country.
Jeffrey Feltman, U.S. assistant secretary for Near Eastern Affairs, was scheduled to meet Wednesday with senior Yemeni officials during a visit to Yemen.
CNN's Brian Todd contributed to this story.