(New York) - Syria should immediately release all those detained on March 16, 2011, when security services violently dispersed a peaceful protest calling for the release of political activists, Human Rights Watch said today. The government should respect the right of Syrians to assemble peacefully and release all prisoners detained for peaceful political activity or for exercising their right to free expression, Human Rights Watch said.

A group of about 150 people, most of them human rights activists and relatives of political detainees, gathered outside the Interior Ministry in Damascus at about noon to present a petition calling for the release of Syria's political prisoners. When the families started raising pictures of their detained relatives, security officers dressed in civilian clothes attacked with batons, dispersing the demonstrators, three participants told Human Rights Watch. Security services detained at least 34 people, according to a list prepared by demonstrators. Human Rights Watch was able to verify independently the detention of 18 people.

"President Bashar al-Asad's recent calls for reform ring hollow when his security services still beat and detain anyone who actually dares to call for reform," said Sarah Leah Whitson, Middle East  director at Human Rights Watch. "Instead of beating families of Syria's political prisoners, President al-Asad should be reuniting them with their loved ones."

A human rights activist who was at the demonstration described what happened:

When we got to the ministry, we could see that there were a lot of security services around. I saw five buses full of security members parked 300 meters from us. At first, an employee from the Ministry of Interior came out and told us that the families of the detainees would be allowed to present the petition to the minister. We asked for five minutes, as some families were still arriving. When a few families raised photos of detained relatives, the security services suddenly attacked us and beat us with black batons.

The daughter of a prominent political detainee told Human Rights Watch:

We had barely taken my father's picture out when men ran toward us and started beating us. They beat my mother on her head and arm with a baton. They pulled my sister's hair and beat her as well until my uncle managed to get her away. We started running away, but they followed us.

One of the people detained during the demonstration, who spoke with Human Rights Watch following his release, said that security services detained him with five others and transported them to the Mantaqa branch of Military Security. The six were: Mazen Darwish, a human rights activist and head of the Syrian Center for Media Freedom of Expression in Syria; Suheir al-Atassi, a prominent political activist; Naheda Badawi; Bader Shalah; Naret Abdel Kareem; and a boy in his early teens whose name was not known. Security services hit Shalah with a baton over his eye, causing bleeding.

At the Mantaqa branch, the detainee who spoke with Human Rights Watch saw four other detainees from the protest: Kamal Sheikho, Usama Nasr, Nedal Shuraybi, and Muhammad Dia' Aldeen Daghmash. The detainee said that security services interrogated each person separately and asked him for the password to his Facebook account. The person who spoke with Human Rights Watch said that as far as he knew, he was the only one released from the group detained at the protest.

In addition to the confirmed 10 detainees at Military Security, Human Rights Watch spoke with a relative of Kamal al-Labwani, a political activist serving a 12-year jail term, who provided details on the detention of seven members of their family: Omar al-Labwani, 19; Yassin al-Labwani, 20; Hussein al-Labwani, 45; Ammar al-Labwani, 24; Ruba al-Labwani, 23; Layla al-Labwani, 56; and Heba Hassan, 22. Their whereabouts are unknown.

One of the demonstrators told Human Rights Watch that she saw security services detain a young man from the al-Bunni family as he was trying to get into his car. The young man's first name is unknown.

"If President al-Assad is serious about reform, he should hold his security services to account," Whitson said. "Syrians deserve no less than the Egyptians and Tunisians who finally succeeded in forcing their political leadership to disband the feared state security services."