A multi-storey Adelaide police station has been evacuated after staff heard a rumble in the building and cracks started forming, but the cause remains unknown.

The building in Sturt, south of the city, was cleared after officers heard “a rumble” and saw structural movement in the western end of the site.

“The building is currently closed and will need to be inspected before normal operations can resume,” SA Police said in a statement on Wednesday.

Police said there were no injuries reported after the evacuation, and there were no members of the public or prisoners on site at the time.

Station officers are now working out of neighbouring commands and counter services are being run out of a police operations vehicle in the car park.

The inspection is not expected to occur until Wednesday afternoon, with police to assess a longer-term plan once more information is known.

There was no record of any earthquake in the area around the time of the incident.

The Sturt police station building was opened in June, 1996.

Officers at the Sturt Police Station in Adelaide’s south last night noticed “what appeared to be structural movement” at the western end of the building.

The police station, on Sturt Road between South and Marion roads, remains closed and will require a building inspection before staff can move back in.

Police said no-one was injured, and no members of the public nor any prisoners were at the station when the incident occurred.

They have described the evacuation as a “precaution” and said police patrols were currently operating out of neighbouring stations.

“It’s a bit of a concern. ‘Round about 7:00pm patrols were inside the station when they heard a rumble,” Senior Constable Mick Abbott told ABC Radio Adelaide.

“The police station is going to be inspected this morning and then hopefully normal operations can resume, but at the moment the station is closed.

A car crashed through the building in 2016.

“Obviously [they’ll] get engineers or someone to have a look at it and hopefully it’s not too bad, but we’ll have a bit more information later on today.”

There had been speculation on social media the cracking and rumble might have been the result of an earthquake, partly because of previous seismic activity in the area.

However, authorities have suggested that was not the case.

“Geoscience Australia has not detected any earthquakes in the region at that time,” a spokesperson for the agency said.

Staff remaining at the site have been forced to operate front counter services from a vehicle in the carpark.

“Members of the public who do not have urgent business or who are able to are asked to attend another station,” police said.

The station is not far from the Darlington road project, where rain damaged concrete installed as part of a $620 million upgrade, causing it to crack and slide.

Access to the station has been restricted following the incident.

In May 2016, a car crashed into the front of the station, smashing two automated glass doors during the early morning.

Darlington was the epicentre of Adelaide’s 1954 earthquake which measured 5.5 on the Richter scale and was widely felt across Adelaide.

After the quake, some buildings in the southern suburbs were demolished due to cracking.

-ABC