Brazilian police shot dead eight people in one of Rio de Janeiro's biggest slums on Monday, an official said, just days after figures showed a record number of killings by state officers in the first quarter.

"We confirm that eight suspects were killed in an operation in Mare," a police spokesman told AFP.

No other details about the operation in Mare - a poor, densely populated swathe of the city in large part run by heavily-armed drug traffickers - were immediately available.

The operation comes after the state Institute for Public Safety released figures on Friday showing 434 people were killed during "police intervention" in the first three months - a 17.9% increase as compared with the same period in 2018.

That is the highest quarterly figure since record keeping of police-related killings began in 1998.