The Syrian military has encircled the central city of Hama, according to media reports two days after the city hosted what many consider to be the largest single protest against President Bashar al-Assad in several weeks of unrest.

Almost 100 military vehicles, including tanks and personnel carriers, carrying thousands of soldiers moved into position on Saturday night, Rami Abdel Rahman of the Syrian Observatory for Human Rights told AFP.

Rahman said residents report that arrests were made on Saturday, the same day state-run news agency SANA announced that Hama's governor, Ahmed Abdul-Aziz, had been sacked by the government.

Activists estimate around 300,000 people rallied in the town on Friday, which would make it the largest single demonstration since a civil uprising began in March. Since then, human rights organizations estimate some 1,400 people have been killed.

Human rights lawyer Razan Zaitouna told Reuters news agency that 24 civilians were killed in Friday's protests, which were held in 172 other locales.

Crowd estimates and other details in Syria cannot be independently verified. The Syrian government has banned most foreign media from the country and restricted coverage.

Hama, which also suffered some 65 deaths when troops fired on a demonstration last month, carries important symbolism as a centre of resistance.

In 1982, Assad's late father, Hafez Assad, stormed the city to crush an uprising, leaving between 10,000 and 25,000 people dead, rights groups say.

Assets frozen in Switzerland

Meanwhile, the Swiss government has confirmed it has frozen 27 million Swiss francs ($30.5 million) linked to senior Syrian officials.

A spokeswoman for Switzerland's State Secretariat for Economic Affairs, Antje Baertschi, said Sunday the assets were identified as part of the Swiss sanctions imposed against Syrian President Bashar Assad and 22 other officials.

Switzerland has taken similar measures to freeze funds linked to the regime of Libyan leader Moammar Gadhafi and deposed Egyptian President Hosni Mubarak.

With files from The Associated Press