U.S. accuses Syria of 'horrific tactics'

BEIRUT -- The United States accused the Syrian government of using "new horrific tactics" yesterday, as UN observers reported helicopters were firing on rebellious areas and concerns mounted that civilians were trapped in besieged cities.

Violence has spiked in recent weeks, as both sides ignore an internationally brokered cease-fire that was supposed to go into effect April 12 but never took hold.

State Department spokeswoman Victoria Nuland expressed concern about reports the regime "may be organizing another massacre" in Latakia province, where UN monitors have been impeded.

Speaking to reporters in Washington, Nuland warned, "People will be held accountable."

Activists reported more than 50 people killed Monday across Syria, with clashes between military forces and rebel fighters in Homs, Idlib and Latakia provinces. The death toll and the online videos were impossible to independently verify.

According to videos posted online, fireballs of orange flame and black rubble exploded in the air as waves of shells pounded residential buildings Monday in the central city of Homs.

Syrian soldiers chased down and killed rebels who set fire to one of their tanks in a farming area close to the Orontes river in Idlib province, said Rami Abdul-Rahman of the Britain-based activist group Syrian Observatory for Human Rights, which uses a network of sources on the ground.

The attack killed seven soldiers and a civilian, he said. There was no confirmation from state media. Another three men and two women were killed while trying to flee, Abdul-Rahman said.

In the nearby village of Laj, another 11 slain men lay in a room, their names scrawled on papers tucked into their clothes, according to amateur video.

A car bomb exploded in the city of Deir al-Zour, killing 10 people, Abdul-Rahman said.

"What we are seeing right now are fierce clashes as the Syrian army tries to take back positions held by the rebels," Abdul-Rahman said. "There are many deaths in the rebel ranks," he said.