The death toll in the storms which devastated part of Brazil' s Rio de Janeiro state this week reached 600, authorities informed on Saturday.

The storms are the worst natural disaster in Brazil' s history, surpassing a flood occurred in 1967 in Caraguatatuba, Sao Paulo state, in which 436 people died.

According to the authorities, the deaths are concentrated in five towns in the state' s mountain range region. So far, 267 deaths were registered in the town of Nova Friburgo, 260 in Teresopolis, 53 in Petropolis, 18 in Sumidouro, and two in Sao Jose do Vale do Rio Preto.

However, as many neighborhoods remain inaccessible due to mudslides, the death toll is likely to be much higher, authorities stated.

Water distribution and electricity are still scarce in the region, as are telephone services. The rescues are being carried out by firemen, Civil Defense workers, Army soldiers and men from the National Security Force. The Navy and the Fire Department set up three field hospitals to treat the injured, as local health care facilities are full, and some have been damaged by the storms as well.

Earlier in the week, Rio' s Environment Secretary Carlos Minc described the storms as a tragedy, and a mix of natural disaster and political irresponsibility.

The occupation of hills and river banks in the mountain range region is a common practice, and one can find both poorly made houses and rich constructions in those areas. The indiscriminate occupation,

combined with the high amount of rain that usually falls in Brazil during the summer, leads to frequent floods and huge mudslides.

President Dilma Rousseff declared three days of official mourning in honor of the victims of the storms. Rio' s governor Sergio Cabral declared seven days of official mourning in the state.

The rain is still falling in the region and is expected to continue in the next few days.