The leader of Yemen's secessionist Southern Movement was arrested in Aden and shots were fired at a demonstration in Sanaa on Sunday as unrest hit the country for a ninth consecutive day.

Thousands of people also staged sit-ins in the cities of Ibb and Taiz, demanding the departure of President Ali Abdullah Saleh, who renewed his call for opposition parties to pursue a dialogue with the government.   

Saleh has held power for 32 years in the country that faces soaring unemployment, dwindling oil and water reserves, and chronic unrest in northern and southern provinces.   

Hasan Baoum was arrested in the southern port city by an "armed military group" in a hospital where he was receiving treatment and was taken to an unknown location, his youngest son Fadi Hasan Baoum told Reuters.   

Baoum was also arrested in November last year, accused of planning illegal demonstrations.   

Security in Aden was stepped up on Sunday with tanks and armoured vehicles out on the city's main streets. In the capital, as many as 50 government supporters tried to break up a demonstration outside Sanaa University by more than 1,000 protesters.

A Saleh supporter fired shots from an assault rifle but there were no reported casualties and the government supporters soon dispersed, while the protesters continued their demonstration chanting, "Leave, Ali!"    

Both sides fired weapons on Saturday outside the university -- the first reported use of firearms by demonstrators.
Several protesters were hurt in those clashes and five people including young girls were wounded in the southern town of Sheikh Othman, apparently by stray bullets.

Five soldiers were wounded on Saturday evening in Khormaksar and Sheikh Othman when protesters clashed with security forces, a local official and witnesses said on Sunday.

In the southern city of Ibb, around 1,000 protesters set up camp in Freedom Square waving banners which read "Leave" and "The people want the fall of the regime", witnesses said.

In Taiz, thousands continued a sit-in for the ninth straight day. Twelve Yemeni human rights organisations demanded the sacking and trials of security officials in Aden, Sanaa and Taiz because of their role in attacks against demonstrators, according to a statement seen by Reuters.   

Saleh on Sunday renewed his call for opposition parties to continue their dialogue and blamed the last two days of protests, in which five people were killed, on "elements outside the system and the law".  - Reuters