Police attended an address at Mayfield Avenue, Carlisle, just after 8pm tonight (April 21).
Inside the address what is believed to have been a pepper spray-type substance had been discharged.
A Cumbria Police spokesman said: “Firefighters and paramedics were also called to the scene as a precaution and the premises made safe.
“There was no risk to the wider public.
“There are not believed to be any serious injuries at this time.
“Two men, aged in their twenties, were arrested in connection with the incident and are in custody tonight.
“Police enquiries continue.”
A Cumbria Fire and Rescue Service spokesman said: “At 8:24pm firefighters were called to a report of a hazardous materials incident on Mayfield Avenue, Carlisle.
“Crews used Breathing Apparatus and Gas Tight Suits to locate the source of the hazard and ventilate the property.”