A pair of disturbances in Hanover resulted in an apartment building being evacuated, police officers and other people being taken to hospital, one person being taken into police custody, and parts of the case remaining unsolved.

Hanover Police say the first disturbance call brought them to an apartment building on 12th Street around 4:45 a.m. Tuesday.

When they arrived at the building, they say, a “strong unknown chemical odour” was coming from the stairwells and responding officers “developed respiratory distress.”

At that point, the building was evacuated.

Moments later, police were notified of a man who was knocking on doors and windows while not dressed properly for the cold morning.

That man was tracked down and arrested, then taken to hospital for treatment. Police say he seemed to be under the influence of drugs.

The 30-year-old Hanover man now faces charges of assault and breach of probation.

Also ending up in hospital were two police officers and some of the people who had been evacuated from the apartment building.

The substance in the building’s stairwells was later found to be bear spray.

Residents of the building were allowed back inside around 6 p.m.

Police say they’re still investigating, and want to hear from anyone who has investigating about the bear spray or the disturbance at the apartment building.