BEIRUT — Syrian troops kept up attacks on the restive city of Hama today, the start of the Muslim holy month of Ramadan, a day after a brutal crackdown on anti-government protesters killed at least 70 and drew harsh rebukes from the U.S. and Europe.

Sunday was one of the bloodiest days since the uprising against President Bashar Assad’s authoritarian rule began in mid-March. Six Syrian rights groups said in a joint statement that 74 people were killed throughout the country, 55 of them from Hama and neighboring villages.

The European Union was preparing new sanctions targeting Syria, the French Foreign Ministry spokeswoman said today.

“Residents are committed to resistance through peaceful means,” Hama-based activist Omar Hamawi said today.

The city’s streets are full of barriers as well as thousands of men “who are ready to defend the city with stones,” he said. “People will not surrender this time,” he said.