KATHMANDU, Nepal (AP) — Rescuers were struggling Monday to reach villages in southern Nepal cut off by a wind- and rainstorm that killed at least 28 people and injured hundreds more.

High winds during Sunday night's storm flipped cars and blew one passenger bus off a highway, causing fatalities. At least 40 people were on the bus. Police said most of the deaths were caused by collapsing walls and falling bricks in homes and toppled trees and electricity poles.

The rainstorm swept through villages in a farming region of Bara and Parsa districts. The government administrator in Bara, Rajesh Poudel, said Monday morning that 27 were killed there. One person died in neighboring Parsa, administrator Narayan Bhattarai said.

Prime Minister Khadga Prasad Oli cancelled his visit to western Nepal and was flying to the area to observe the rescue efforts, his office said.

The National Emergency Operation Center in Kathmandu said 612 people were injured and teams with tents and other material have been sent to the villages.

The weather was clearer Monday morning, which was expected to allow helicopters to begin bringing the injured from their villages to medical facilities.

Police official Sanu Ram Bhattarai said police officers and soldiers from neighboring areas had reached the districts Monday and were trying to reach the villages.

Poudel earlier said the number of deaths would likely increase as the storm had hit many villages in Bara, about 120 kilometers (75 miles) south of the capital, Kathmandu.

Local television showed the injured being brought to a hospital by cars, ambulances and even motorcycles, but roads in many villages had been blocked by fallen trees and electricity poles.

The Department of Hydrology and Meteorology's forecasting division had forecast heavy rainfall with thunderstorms in the general southern region.

Division official Sujan Subedi said, however, the forecasting office doesn't have the technology to predict storm conditions in specific areas and the forecast is generally for the entire region.

He also noted March and April commonly had pre-monsoon storms strong wind with rain.

The provincial government also announced 300,000 rupees ($2,725) in financial assistance for the families of each of the dead.