Nelson Hospital was placed into lockdown this afternoon following an incident at nearby Franklyn St.
Police say it advised the hospital to be locked down after locating a vehicle whose driver had earlier been seen with a firearm.
"Shortly after 1pm a man indicated to security staff that he had a firearm, outside Nelson District Court," police say.
"The man left the area in a vehicle, which police located on Franklyn Street, Nelson South near Nelson Hospital at around 1.15pm.
"Police advised Nelson Hospital to lockdown until the incident could be resolved."
Police says three people were taken into custody soon afterwards, and they are assisting them with enquiries.
It says the hospital lockdown has since been lifted and while no firearm has been located, their enquiries are ongoing.
"There is not thought to be any ongoing safety concerns for the public."
Te Whatu Ora - Nelson Marlborough has been contacted for comment.
