Yemen's Interior Ministry denied reports that southern separatists escaped from a police station in the southern city of al-Dhalea after a blast at the building on Thursday, dpa reported.
Earlier in the day, local sources said around 30 members of the secessionist Southern Movement fled after a bomb blast rocked the building.
The ministry said in a statement that six detainees were injured after one of them detonated a hand grenade. It said the reports on the escape were "completely untrue and baseless."
It said the six were among 20 "saboteurs" arrested earlier in the day over their participation in an unlicensed demonstration in al-Dhalea, some 260 kilometres south of the capital Sana'a.
Witnesses said police exchanged fire with armed separatists outside the detention centre after the explosion, but made no reports about casualties.
In the southern district of Radfan, around 30 kilometres south of al-Dhalea, two people were killed and a policeman injured in clashes after a rally in the district's main city of al-Habileen, a local source said.
Violent protests have rocked several cities in southern Yemen in the last few months, leaving dozens of dead and wounded among both the protesters and security force members.
The protests were organized by southern secessionist groups claiming that the central government exercises discriminatory policies against southerners.
North and South Yemen were united in 1990. In 1994, southern leaders announced the secession of the south and battled northern forces led by President Saleh for 10 weeks in a civil war that ended in their defeat.
The violence highlights the increasing discontent by the southerners and tensions between southern and northern Yemen 16 years after the civil war.
Yemen denies prison escape in southern city after blast (UPDATE)
Yemen's Interior Ministry denied reports that southern separatists escaped from a police station in the southern city of al-Dhalea after a blast at the building on Thursday, dpa reported.
