Yemeni soldiers battled al-Qaida-linked militants Monday outside the southern city of Zinjibar, which remains partly under the control of the Islamists. Five soldiers and four fighters were killed, a military official said.

The intense fighting in northern and eastern Zinjibar included artillery and rocket shelling on militant hideouts, the official said, speaking on condition of anonymity in line with military regulations.

He said the military units were engaged in pitched battles with armed gangs deployed on the streets, and have advanced on areas controlled by the militants.

At least 60 people, including 23 soldiers, have been killed in the fighting since last week.

Islamic militants, including some with links to the al-Qaida branch in Yemen, seized control of Zinjibar and another town in April and May. They were taking advantage of the turmoil surrounding the popular uprising against President Ali Abdullah Saleh to expand their area of operations.

Al-Qaida in the Arabian Peninsula was behind several nearly successful attempts to attack U.S. targets, including the failed attempt to down a passenger jet bound for Detroit on Christmas Day 2009. Washington believes it is the most dangerous of several al-Qaida's offshoots around the globe.

President Saleh has cooperated with the U.S. in fighting the group and used the threat of al-Qaida in arguing that he could not relinquish power in Yemen despite the protests calling for him to go since February.

The U.S. withdrew its support of Saleh in the summer, and the autocratic leader signed a deal last month to transfer power in exchange for immunity from prosecution over the deaths of protesters and corruption during his 33 years in power.

The deal has failed to quell the protests in Yemen, which have recently expanded to include labor strikes, calling for Saleh loyalists to be removed from office and for Saleh to be put on trial.

On Monday, Yemen's military agreed to replace a commander accused of corruption, apparently settling a brief strike by 1,000 soldiers, said Anwar Abdullah, an officer in a military department that deals with public affairs and army morale. Abdullah said that the strikers demanded the ouster of department head Maj. Gen. Ali al-Shater for mismanagement, accusing him of running his own prison, in which some soldiers were jailed even for minor offenses. Some were kept in chains.

Abdullah said after the prime minister intervened in the dispute Monday, it was agreed that al-Shater would be replaced.

The soldiers said they would end their strike when the defense minister appoints a new commander.