BEIRUT // Activists seeking to break the iron-fist rule of Syria's president called Saturday for daily protests after at least 32 people were killed in the single bloodiest day since the uprising began three weeks ago.
The rallying cry by protest leaders was met with a sharp warning by Syrian authorities that they would crush further unrest, raising the risks of further bloodshed as President Bashar Assad's regime faces unprecedented challenges to its sweeping authority.
Most of the dead from Friday's violence were reported in the restive southern city of Daraa, where burials were planned Saturday. Rights activists and witnesses say security forces opened fire on tens of thousands of protesters in Daraa, killing 25 people and wounding hundreds.
State-run TV offered a different account, saying 19 policemen and members of the security forces were killed when gunmen opened fire on them. It was the first significant claim of casualties by the Syrian government, which has claimed that the unrest is driven by armed gangs - rather than reform seekers - and could signal plans for stronger retaliation and crackdowns.
The accounts could not be independently verified. Syrian authorities have banned most journalists from entering the country and tightly control others inside.
Activists on social network sites called the protests to pick up pace with rallies and marches each day. So far, demonstrations had largely been confined to Fridays.
In a signal of an increasingly tough line, Syria's Interior Ministry said it will not tolerate "the intentional mixing between peaceful protests and sabotage and sowing sectarian strife."
"Syrian authorities will confront those people and those that stand behind them," the statement added.
The calls for reform have shaken Assad, whose family has ruled Syria for more than 40 years.
As the wave of protests have gathered steam, Assad has offered some limited concessions - firing local officials and forming committees to look into replacing the country's despised emergency laws, which allow the regime to arrest people without charge. On Thursday, he granted citizenship to thousands of Kurds, fulfilling a decades-old demand of the country's long-ostracized minority.
But those gestures have failed to appease a growing movement that is raising the ceiling on its demands for concrete reforms and free elections.
At least 32 protesters were killed nationwide on Friday, according to human rights activists. The bloodshed lifted the death toll from three weeks of protests to more than 170 people, according to Amnesty International.
President Barack Obama in a statement Friday night condemned the violence and called on Syrian authorities to refrain from attacks on peaceful protesters.
"Furthermore, the arbitrary arrests, detention, and torture of prisoners that has been reported must end now, and the free flow of information must be permitted so that there can be independent verification of events on the ground," Obama said.