The men were among at least seven soldiers kidnapped by gunmen to protest a southerner's sentencing to death on accusations of bombing an Aden soccer club in October, which killed four people, ahead of a regional soccer tournament hosted by the country.

Protests have paralyzed south Yemen towns known to be secessionist strongholds since the court handed down a death sentence to Faris Abdullah Saleh on Saturday.

The release of the six soldiers kidnapped in the town of Dhalae came on condition that Faris Abdullah Saleh be given a fair trial when he appeals his sentencing.

Protests continued for a third day in Dhalae and shops and restaurants remained closed, residents said.

North and south Yemen formally united in 1990 but some in the south, home to many of Yemen's oil facilities, say northerners have seized their resources and discriminate against them.