|Opposition activists have called on Syrians to protest every day in solidarity with the city of Deraa [Reuters]
Syria has called on citizens "misled" into acting unlawfully to turn themselves in, in return for exemption from prosecution, as security forces continue to crack down on protests against President Bashar al-Assad's government.
Dozens have been killed in recent days, according to activists, and hundreds arrested as Syrian army units continue to lay siege to the southern city of Deraa and other flashpoint cities across the country.
Security forces rounded up on Monday hundreds of pro-democracy sympathisers - including a prominent human rights campaigner, Diana Jawabra, for the second time during the ongoing uprising, news agencies reported.
"I am Dana Jawabra from Deraa," she shouted as she was forced into a white car belonging to the secret police outside her home in the West Mezzeh district of Damascus.
Monday's arrests came as Assad met the visiting UAE foreign minister, Sheikh Abdullah bin Zayed Al-Nahyan, and told him "measures are being taken to overcome the current situation and strengthen the process of reforms in all fields", according to a report by the state news agency SANA.
Anti-government protesters, inspired by a wave of unrest across the Arab world, are demanding greater freedoms and an end to Assad's decade-long presidency and the Baath Party's near-50-year grip on power.
Activists have planned fresh anti-government demonstrations following the deaths of dozens of people in weekend protests.
A humanitarian aid convoy bound for Deraa from Syria's Jordanian border was due to depart on Monday afternoon in a bid to reach the city of 125,000 which has been without electricity and communications since April 26.
Activists say food, water and medical supplies are in short supply in Deraa.
Opposition activists have called on Syrians to protest every day at noon in solidarity with Deraa and all "besieged" towns.
But Syria's government accuses "armed groups and terrorists" of attempting to foment unrest. In a statement on Sunday evening, the interior ministry offered an amnesty until May 15 for citizens caught up in the revolt to hand themselves in.
The ministry told "citizens who have participated in or committed unlawful acts such as bearing arms, attacking security or spreading lies to surrender by May 15 and hand their weapons in to the competent authorities".
It further urged Syrians to "supply information about saboteurs, terrorists and arms caches", pledging "they will be spared any subsequent legal consequences".
Government security forces were again making their presence felt on the streets overnight, with a military source on Monday announcing the arrests of 499 people in Deraa.
Ten "terrorists" and two security force members died in Sunday's clashes, the source told SANA.
In Damascus, the capital, a witness told Al Jazeera that tanks had surrounded the suburb of Daraya.
Activists said security forces had also moved into Kafar Nubbol, 320km north of Damascus, at dawn on Monday, arresting 26 people in the capital and in the eastern city of Qamishli.
Rights groups claim the civilian death toll since protests began in mid-March has topped 580.
Neighbouring Turkey said on Monday that it was preparing for a possible influx of Syrian refugees into its southeastern Hatay province. Abdullah Gul, the Turkish president, said his country was preparing for the “worst-case scenario”.
Alain Juppe, the French foreign minister, added his voice to the growing clamour of international condemnation of Damascus.
"If the regime perseveres down this path, it will fall, one day or another, but it will fall," Juppe told Europe 1 radio on Monday.
"Today there is this great hope for freedom and democracy. You must take this into account and putting it down by firing live rounds into crowds is unacceptable, whichever country does it."