Hundreds of Rio slum dwellers fled their homes overnight, choosing to sleep in streets away from their own neighborhoods after rumors spread drug gangs were set to battle again.

Police say at least 29 people have died in the northern area of the city since this weekend. Three suspects were shot dead by police early Wednesday. But the area was relatively calm by midday.

The clashes began last weekend when a drug gang tried to invade a rival's territory.

Three police have died in a helicopter that was shot down by gunfire.

The fighting comes just two weeks after Rio won the 2016 Olympics.