Journalist Samia al Aghbari (foreground in a blue jacket) and parliament member Ahmed Seif Hashid (behind her in a black leather jacket) struggle with members of the Yemeni security forces attempting to arrest them.

(Sanaa) - Yemeni security forces used electroshock stun guns and batons against peaceful anti-government demonstrators in the capital, Sanaa, on February 13, 2011, Human Rights Watch said today.  Human Rights Watch called on the Yemeni government to cease all attacks against demonstrators and investigate and prosecute those responsible.

"Without provocation, government security forces brutally beat and used stun guns on peaceful demonstrators on the streets of Sanaa," said Sarah Leah Whitson, Middle East and North Africa director at Human Rights Watch. "The government needs to take full responsibility for this abuse."

Protesters told Human Rights Watch that an anti-government demonstration organized by local, independent activists began at 10 a.m. on February 13 at the new Sanaa University. Soon more than 1,000 demonstrators were calling for Yemen's president, Ali Abdullah Saleh, to resign.

Dozens of pro-government thugs, known locally as balataga, arrived and attacked the demonstrators. To avoid a clash with the balataga, the anti-government demonstrators began a march.

When the demonstrators reached the Rowaishan intersection in Sanaa, at about 1 p.m., they said they were met by several hundred uniformed government paramilitaries from the Interior Ministry's Central Security Organization, who were carrying batons, military assault rifles, and teargas guns. Without issuing a warning, the security forces charged the demonstrators, swinging their batons at demonstrators, who fled.

Members of the security forces used batons to beat at least 20 demonstrators on their heads and backs, and beat and kicked others. They attacked two demonstrators with stun guns, witnesses told Human Rights Watch.

Mizar Baggash Ghanem, a student leader at Sanaa University, told Human Rights Watch that the security forces used a stun gun to shock him from behind. His back bore several fresh red wounds. Security forces attacked and threw to the ground Samia al Aghbari, an activist and journalist, who collapsed unconscious after her head hit a curb. She was taken to a hospital. The security forces also attacked leading activist Khaled al Anisi with an electroshock stun gun, arrested him, and then released him. Faez Noman, a youth activist, alleged that security forces beat him with batons on his back and wrist, which showed fresh bruises.

Witnesses also told Human Rights Watch they saw security forces beat a youth on his head, causing bloodshed, and then arrested him. Security forces arrested several young demonstrators, including two who appeared to protesters to have been severely beaten.

Human Rights Watch called upon the Yemeni authorities to abide by the United Nations Basic Principles on the Use of Force and Firearms by Law Enforcement Officials, which provide that all security forces shall, as far as possible, apply nonviolent means before resorting to the use of force. Whenever the lawful use of force is unavoidable, the authorities must use restraint and act in proportion to the seriousness of the offense.  The authorities should investigate and punish the arbitrary and excessive use of force by its security forces. Additionally, the Yemeni government has an obligation to recognize and protect everyone's right to peaceful assembly and free expression.