The violence by Syrian security forces against pro-democracy protesters has triggered the unprecedented resignation of 200 members of the ruling Ba’ath Party.
Most of those quitting come from the city at the centre of the unrest, Deraa.
President Bashar al-Assad is leader of the party, which has ruled Syria under him and his father before him, since taking power in a 1963 coup.
In a separate declaration a further 28 Ba’athists in the city of Banias also resigned over what they called the murder and torture of honourable citizens.
International criticism has grown over the aggression meted out with the UN having called for an investigation into the alleged 450 deaths since the unrest began.
And the storming of the city of Deraa over the weekend has sharpened anger in Europe. Many countries have called for sanctions against Damascus and yesterday summoned Syrian ambassadors to protest at the killings.