Seventy two percent of Rio de Janeiro residents said they would leave their city if possible due to fear of violence, an opinion poll published Saturday said.

The poll from the respected Datafolha firm was conducted last week in the aftermath of heavy media coverage of an army operation against drug trafficking gangs in Rio's huge Rocinha favela.

According to the poll, which was published in Folha de Sao Paulo newspaper, 67 percent of residents in Brazil's biggest tourist destination said they had heard gunshots recently.

Ninety percent said they felt unsafe walking outside at night. With stray bullets hitting Rio residents far from the confrontations between police and criminals, 24 percent said they knew a friend or relative who was a victim of gunfire.

There was also overwhelming criticism of the authorities, who have struggled to stem rising crime and economic decline in the wake of the 2016 Rio Olympics.

Seventy four percent of those polled said that Rio state Governor Luiz Fernando Pezao was doing a "bad" or "very bad" job when it comes to security.

The survey questioned 812 people and had a margin of error of four percent, Datafolha said.