Anti-government protesters in Syria are planning further demonstrations during the week, undaunted by a violent security crackdown unleashed on them.
Activists, vowing to keep up the pressure on the regime of President Bashar al-Assad, said the "week of breaking the siege" protests would begin in Deraa on Sunday and around the capital, Damascus, on Monday.
They were referring to the brutal lockdown imposed on the southern city of Deraa and in the Damascus suburb of Douma by the authorities in a bid to quell the unprecedented protests.
Hundreds have been killed in the weeks since the protests first erupted, shaking Assad's one-party rule.
Rallies are planned in the northern towns of Baniyas and Jableh on Tuesday, while protests are planned on Wednesday in Homs, Talbisseh and in Tall Kalakh on the border with Lebanon. Nationwide night vigils are also to be held on Thursday.
The determined call for renewed protests came as security forces continued to come down heavily on the protesters.
Quoting a source in Deraa, Al Jazeera's Rula Amin said the situation in the city remained tense though tank shelling had ceased.
"Security forces are intensifying their house to house searches and (there have been) many many random arrests.
"He says hundreds of people have been arrested...government says it's forces arrested 149 people in Deraa. Old city and the Karak neighbourhood are bearing the brunt of the operation today."
'Symbol of defiance'
Deraa has been tightly blockaded since Monday, when the army went in backed by snipers and tanks.
"In Deraa, people are still confined to their homes, communications still down, no electricity, no one can go in and no one can come out," our correspondent added.
"Deraa is where the protests started, it has become a symbol of defiance, of resistance.
"Deraa is where the protests started, it has become a symbol of defiance, of resistance"
Rula Amin, Al Jazeera correspondent
"But no matter how panicked, or concerned they (the protesters) are, they say that their morale is still high.
"They want pressure to be put on the government to end the crackdown, to end the seal to Deraa... but people say that they are better off without any intervention, they are very critical of US."
Meanwhile, Syrian rights groups urged the authorities on Sunday to release a prominent opposition figure seized by security forces the previous day despite the lifting of emergency rule.
"Syrian authorities arrested prominent human rights activist Hassan Ismail Abdel Azim on Saturday from his office and took him to an unknown destination," the National Organisation for Human Rights in Syria said.
Earlier, Syrian forces seized control of a mosque in Deraa, shooting dead the son of its imam, witnesses said.
Four people were reportedly killed as the southern city came under heavy shelling and gunfire on Saturday, as residents attempted to bury those killed a day earlier during Friday's "day of rage" protests against the government.
Residents said Syrian forces fired at protesters in neighbourhoods throughout the city, as tanks reportedly surrounded the Omari mosque in the north.
Witnesses later told the Reuters news agency that Syrian forces had stormed the mosque, following heavy shelling.
Al Jazeera could not independently corroborate the witness accounts.
'Government reform plans'
Al Jazeera correspondent said the latest developments reveal how quickly the situation in Deraa is deteriorating.
"In the past few days, Syrian television has been putting people on television saying that they are confessing that they belong to terrorist groups and that they were given money and weapons from different people in Deraa, including the imam of the Omari mosque," she said.
In Damascus, about 50 women marched near the parliament, holding signs in support of Deraa. Rights campaigners said eleven of the demonstrators were arrested.
Meanwhile, Adel Safar, the recently appointed prime minister, said his government would draw up a "complete plan" of political, judicial and economic reforms, state news agency SANA reported.
SANA quoted Safar as saying he would set up committees to propose new laws and amendments to legislation in those areas.