Syrian police arrested the country's leading rights lawyer and five other activists on Wednesday, bringing to nine the number of people detained this week in what a rights group described as the largest roundup of democracy campaigners in years.
All but one of the nine had signed a petition calling for an improvement in relations with Lebanon.
The lawyer, Anwar al-Bunni, was dragged away from his home by security police, his family said. His brother Akram al-Bunni said that the lawyer was leaving home for an English class late on Wednesday when two men asked him to get into their car.
"Anwar asked them to show him an arrest warrant, but they forced him into the car, and drove away while he was shouting [for help]," Akram said.
The Syrian government has not confirmed the arrests. The authorities almost never issue statements about political detentions, regarding them as security matters.
The head of the National Organization for Human Rights in Syria, Ammar Qurabi, said in a faxed statement that he believed most of the detainees were arrested for signing the petition. Only Khaled Khalifa did not sign the letter, which 500 Syrian and Lebanese intellectuals put their names to last week.
State media have condemned the petition, with the official newspaper Tishrin saying on Wednesday that it contained lots of "lies that would never convince any rational person."
The paper's editorial accused the signatories of trying "to imply that Syria is threatening Lebanon." The editorial said it was "suspicious" that their move came as the US was mobilizing support for a UN Security Council resolution calling on Syria to establish diplomatic relations with Lebanon and demarcate their common border.
The Security Council passed the resolution hours after the editorial appeared.
Al-Bunni has often called for democratic reform in Syria and has spoken out on behalf of detainees and Kurdish activists. He has been arrested several times. Among his clients was Aktham Naisse, the leader of a rights group who boldly staged a demonstration outside parliament in March 2004.
Al-Bunni's four brothers have all been detained as communists but Anwar does not belong to any political party, Akram said.
Earlier this week, al-Bunni had publicly condemned the arrest of prominent writer and democracy campaigner Michel Kilo, who was detained on Sunday.
"This campaign [of detentions] will not dissuade anybody from pressing on with their demands," al-Bunni had told the international media. "But it will increase our determination to continue with our mission."
On Wednesday, the police also arrested Mahmoud Issa, a former political prisoner who previously spent eight years in jail; Safwan Tayfour, a doctor active in public affairs; Khalil Hussein, a leader of the Kurdish group Al-Mustaqbal who has previously spent 12 years in prison; activist Abbas Abbas; and Khaled Khalifa, according to the Syrian Organization for Human Rights.
The organization said it believed police may have confused Khalifa with someone else and detained him by mistake.
The organization said two other activists, Suleiman Al-Shammar and Kamal Sheikho, were summoned by police. The group said it did not know whether the two men had heeded the summons, but their whereabouts were unknown.
The National Organization for Human Rights in Syria said the arrests were part of the largest campaign since the crackdown on political activists in September 2001 that ended the "Damascus Spring" which followed President Bashar Assad's taking office in 2000.