Chicago, May 31 (IANS): Two people could still be inside the six-storey apartment building that partially collapsed Sunday afternoon in Davenport, US' Iowa state, in addition to three more people remaining unaccounted for, local authorities have said.

The damage occurred when the back section of the apartment building detached from the rest of the structure, local media quoted Davenport Fire Chief Mike Carlsten. Nine people have been rescued so far, Xinhua news agency reported.

"This is an active incident that is very fluid and ever-evolving," Davenport Mayor Mike Matson said on Tuesday at a news conference.

Protesters gathered on Monday night on news of imminent demolition of the building, saying some residents could still be trapped.

Davenport is "continually evaluating the timing of the demolition", the city said in an update Tuesday.

A condo building collapsed in Surfside, Florida, in 2021, killing 98 people. A parking garage collapsed in April this year in New York City, killing one person and injuring at least five.