Local officials reported the clash in the southern province of al-Bayda.
"Dozens of former members of the Republican Guard left their camp and entered Redaa city with their weapons and cars," one resident said. "They deserted their base and started extorting people before they eventually assaulted a resident," he said, prompting tribesmen to intervene to try and stop them.
A local government official said four soldiers and three armed tribesmen were killed in the clashes.
In a separate incident, tribesmen blew up the main Maarib oil pipeline in south Yemen only two weeks after it was repaired, the interior ministry said.
Yemen's oil and gas pipelines have been repeatedly sabotaged by insurgents and disgruntled tribesmen since anti-Saleh protests created a power vacuum. Fuel shortages resulted and export earnings vital to impoverished Yemen plunged.