Rescue workers on Thursday found two more bodies in the wreckage of a seven-story building that collapsed earlier this week in northeast Brazil, bringing the death toll to four.

Rescue workers carry a victim after a seven-story residential building collapsed in Fortaleza, Brazil, Oct 15, 2019. (Photo: Agencies)

The Andrea Building in Ceara state's capital Fortaleza plummeted to the ground on Tuesday just as the structure was undergoing renovation work.

Fire chief Luis Eduardo Holland told reporters at a press conference that rescuers retrieved the corpse of an unidentified man early in the day.

The body of an unidentified woman was also found, but has yet to be pulled from the rubble.

"We are still working to find six people" reported as missing, said Holland. "We are now looking for a possible sign (of life), working at a point where there could still be people alive."

Some 130 firefighters divided into different groups have been working round the clock, with the help of volunteers, to remove structural material.

Authorities have confirmed the identities of the two initial fatal victims -- Frederick Santana dos Santos, 30, and Izaura Marques Menezes, 81.

Investigations were underway to determine the cause of the collapse.