The Rivers State Government is investigating the incident, says an official.

An appendage of a two-story hotel has collapsed in the Ada-George area of Port Harcourt, Rivers State.

Four people injured from the incident are receiving treatment in hospital.

The News Agency of Nigeria (NAN) gathered that the two-storey building belonging to 1708 Hotel, Rumuoke by Okilton Junction, off Ada George, collapsed at about 6.15 a.m. on Thursday.

The incident occurred when some residents of the area were still asleep, and occupants of the building, who were mainly site workers, were getting ready to resume for the day's job.

Emeka Woke, the Rivers State Commissioner for Works, while inspecting the level of damage and causal effect of the incident, said that the government would take every measure to unravel the immediate and remote causes of the collapse.

"Early this morning, the governor, Siminialaye Fubara, was informed about this building collapse. He directed that I immediately visit the site on his behalf and assess the extent of the damage and report back to him.

"Having seen the building, the first thing we did was carry out a personnel audit and from available records, no life was lost, but we have been told that four persons sustained some injuries and were taken to the hospital for treatment," he said.

The commissioner said that the governor also directed that the premises of the collapsed building be sealed off pending investigation.

He, however, noted that operations were ongoing at the site, basically to evacuate the rubbles.

Isa Aghaebne, an engineer handling the integrity test on the collapsed building, said a structural integrity test would commence on Friday.

He, however, noted that the collapse might be due to foundation failure or failure of the structure itself.

"We can't ascertain now until we have concluded an integrity test, which is expected to last for about two weeks," he said.

NAN gathered that the collapsed building is part of the expansion of an existing building.