Heavy rains since last week have led to the deaths of 72 people in southern Brazil's Santa Catarina state, local civil defense authorities said Tuesday.

A view of the flooded Ilhota city in the Brazilian state of Santa Catarina Nov. 24, 2008. Rescue workers rushed to help stricken residents in southern Brazil on Monday after landslides and floods caused by heavy rain killed at least 59 people and forced more than 43,000 from their homes. The state of Santa Catarina declared an emergency as rescuers used helicopters and motorboats to reach those displaced or stranded by the floods after days of torrential rain. Picture taken Nov. 24, 2008. [Xinhua/Reuters Photo]

Over 55,000 displaced people cannot return to their homes, either because they were destroyed or because their neighborhoods are flooded and blocked by landslides. As many as 30 people are still missing.

Authorities said in a statement that eight municipalities are completely cut off. Landslides have blocked about 20 state and federal roads, making it harder for rescue teams to reach several locations.

Torrential rains have been pounding Santa Catarina for nearly two months, with three times the normal rainfall recorded in November. The showers are not expected to stop at least until Saturday, according to weather forecasts.

Federal Governor Luiz Henrique da Silveira called the downpour the worst natural disaster in the history of Santa Catarina, which has been placed under a state of emergency.

In Itajai, one of the most affected towns, 80 percent of the urban area is under water. In Ilhota, 15 people died over the weekend due to landslides, while 13 people died and 20,000 had to flee their homes in Blumenau.

The rain also damaged power lines in several towns, with the local power company reporting Tuesday afternoon that over 137,000 houses and stores had been without power.

Meanwhile, an explosion triggered by the rains damaged one of the lines of the Brazil-Bolivia natural gas pipeline, disrupting supplies to parts of Santa Catarina and Rio Grande do Sul states. Repairs will take three weeks, said state oil and gas company Petrobras.

President Luiz Inacio Lula da Silva has sent three of his ministers to Santa Catarina to assess the situation and draw up a plan to help the state. The federal government has already sent 286 tons of food, as well as mattresses and blankets to the locals.

Army troops are helping rescue those marooned in isolated areas, with two air force planes airlifting supplies.