Amnesty International has urged the Bahraini authorities to ensure the safety of people participating in peaceful protests and of all detainees after one demonstrator described how police tortured him and his friend repeatedly late last week.

'Abdallah Salman Mohammad Hassan told Amnesty that he and a friend endured torture and other ill-treatment during hours of detention and interrogation after police arrested them in the Bahraini capital Manama on Friday.

The pair were said to have been punched and beaten with sticks by police who questioned them about their role in the protests before releasing them without charge on Saturday evening.

Hassan told Amnesty that he and his friend were stopped in their car at a checkpoint near Manama's Pearl Roundabout. The police reportedly searched the vehicle and found a Bahraini flag with the words "We are staying in the Martyrs (Pearl) Roundabout until our demands are met" written on it.

Hassan says the pair were then beaten and taken to a police station in al-Na'im district where they were again assaulted. Hassan says he was also blindfolded and beaten with a wooden stick after being taken to another police station in al-Gadhaibiya.

Amnesty International Middle East and North Africa Director Malcolm Smart said:

"The Bahrain authorities must respect the rights of people to participate in peaceful protests and to exercise their right to freedom of expression without fear of retaliation, arbitrary arrest, detention or torture.

"They must also investigate the alleged torture and other ill-treatment of 'Abdallah Salman Mohammad Hassan and his friend and hold those found responsible to account.”

Describing his ordeal, 'Abdallah Salman Mohammad Hassan said: "They tied my hands behind my back and then put me on a chair; I was standing on the chair. Then they put my arms behind the door from the top and pushed the chair away. I was left suspended: my body on one side of the door and my arms on the other side. It was very painful. I asked for water and they didn't give it to me. I wanted to pray and they refused. I didn't sleep. I was left suspended on the door for a few hours."

Hassan was interrogated about the protests and held for 30 hours before being released. He went to al-Salmaniaya hospital for X-rays and his right arm was put in plaster. He said his friend was released earlier than him but did not give any details.

The unrest in Bahrain started with a 14 February “Day of Rage” organised on Facebook and Twitter,  apparently inspired by popular protests in Egypt and Tunisia.

At least seven people were killed and scores, possibly hundreds, of people have been wounded in the past week by security forces using excessive force against protestors before they were largely withdrawn on Saturday. Amnesty last week condemned the heavy-handed tactics of Bahrain's security forces.

On 11 February Amnesty highlighted the deteriorating human rights situation in Bahrain in a report, Crackdown in Bahrain: human rights at the crossroads (see: http://bit.ly/i9QFAo). Yesterday the King of Bahrain issued an order to free political prisoners and other detainees. Those released may include 23 opposition political activists who have been detained since their arrest in August and September 2010, and who are featured in Amnesty’s report.