Five regions of the impoverished country have been declared disaster zones following the storm, which struck early on Saturday, the military-run Myaddy television station said.

Of the 351 dead, the report said nearly 222 of them were from the country’s low-lying Irrawaddy delta. The rest were killed in Yangon, which was devastated and left without electricity.

“The Irrawaddy delta was hit extremely hard not only because of the wind and rain but because of the storm surge,” said Chris Kaye, the UN’s acting humanitarian coordinator in Yangon. “The villages there have reportedly been completely flattened.”

The UN is planning to send teams on Monday to assess the damage, he said. Initial assessment efforts have been hampered by roads clogged with debris and downed phone lines, he said.

“At the moment, we have such poor opportunity for communications that I can’t really tell you very much,” Kaye said.

Witnesses in Yangon said the storm’s 120 mph winds blew the roofs off hundreds of houses, damaged hotels, schools and hospitals and cut electricity to the entire city. The state-owned newspaper New Light of Myanmar reported on Sunday that the international airport in Yangon remained shut.

Domestic flights have been diverted to the airport in Mandalay, it said. “It’s a bad situation. Almost all the houses are smashed. People are in a terrible situation,” said a UN official in Yangon.

Criticism

Some Yangon residents who had ventured out on Sunday to buy materials to repair their homes were heard expressing their anger against the military-led government.

The cyclone came at a delicate time for Myanmar, which is scheduled to hold a referendum on May 10 on the country’s military-backed draft constitution.