It is still too dangerous to enter the area where ammunition stockpiles exploded on Sunday in Congo's capital, Brazzaville, rescue workers have said.A BBC reporter in the city says there are fears that hundreds of bodies could be buried in the rubble of buildings.The official death toll stands at 146, with 1,500 people injured.Unexploded shells scattered by the blast's force pose a further risk - and a military source told AFP that fires could spread to a second arms dump.The BBC's Thomas Hubert in Brazzaville says the scene at the edge of the military barracks is one of "utter devastation" - with collapsed buildings and uncleared bodies.The fence surrounding the military base - where the serious of explosions began after 08:00 local time (07:00 GMT) on Sunday and continued into the early afternoon - has been blown away even though it was made of reinforced concrete, he says.Emergency relief is slowly getting organised in the city.The main university hospital is still admitting a steady stream of patients with fractures and blast wounds, our reporter says.Some are lying under tents erected by the medical charity Medecins sans Frontieres outside the main building.CurfewRescuers still searching for survivors and Red Cross officials trying to collect the dead are unable to gain full access because the blast scattered many unexploded devices, our correspondent says.Government officials said Sunday's huge explosions at the ammunition store in Mpili, an eastern suburb of Brazzaville, were caused by a short-circuit that led to a fire.There is a risk of more explosions because there is another arms dump only 100m (109 yards) away apart, an anonymous military source told the AFP news agency.Residents in the east of Brazzaville fled when the first blasts occurred - and at least 2,000 people are now in temporary shelters throughout the city.Some have returned to their homes to try to salvage as many possessions as possible, our correspondent says."We shouldn't have been allowed to live so near the camp," Victoire Ndzota, whose house was wrecked, told Reuters news agency.Government spokesman Bienvenu Okyemi has said the death toll stands at 146, although hospital sources have told the BBC it is more than 200.After visiting two hospitals, visibly shaken President Denis Sassou-Nguesso said the government was doing all it could and urged the Congolese "to show courage and solidarity".He also announced a curfew in the area and set up an exclusion zone.Defence Minister Charles Zacharie Bowao earlier appeared on national TV to urge calm in Brazzaville and across the Congo river in Kinshasa, where windows were blown out and roofs damaged by the blasts.Our correspondent who was in Kinshasa at the time of the blasts says many people fled from the river fearing shelling had broken out in Brazzaville.