Dozens of flood survivors desperate for news of missing relatives lined up outside a morgue in the town of Teresopolis on Saturday as criticism grew of authorities’ response to one of Brazil’s worst natural disasters which has killed nearly 600 people.

Nearly four days after rains sparked floods and massive landslides, officials in this scenic mountain town are still struggling to cope with the scale of the catastrophe. The steadily rising death toll in the region north of Rio de Janeiro hit 591 on Saturday, Brazil’s Civil Defense agency said, and President Dilma Rousseff declared three days of national mourning.

Cemeteries in Teresopolis have been overwhelmed by the number of bodies and Brazilian media reported that residents in isolated areas have been forced to bury victims themselves.