A Christchurch school was sent into lockdown and two streets blocked off after reports of a firearm, which is now thought to have been a paintball gun.

Police received a report of a person with a firearm at an address on Matipo St at about 3.30pm, a spokeswoman said.

A Wharenui School spokesperson said police told them to go into lockdown. She said children at the school were in the after-school care programme.

Officers, along with the Armed Offenders Squad, responded. They had all been stood down by 5pm

Shortly before 7pm a police spokeswoman said nobody had been arrested following the incident and the "firearms" reported were believed to be "paintball-type guns", located.

The manager of Wharenui Swimming Pool and Sports centre said police had first told the centre to go into lockdown at 3.30pm.

MATIPO ST - POLICE OPERATION - 4:30 PM, TUES 4 JUNE
Due to a police operation Matipo Street is closed between Riccarton Road and Blenheim Road.
Road users should avoid this road until further notice. ^SM pic.twitter.com/lLeteV6Y1m

— TFC (@TransportChCh) June 4, 2019

She said she had been told police had caught someone in the Wharenui School Grounds.

Police had earlier posted an officer at the swim centre's front door.

"All we heard earlier on was there was a person out there with a gun," she said.

"We had a lockdown procedure so we kept everyone in the building. Because we've got concrete buildings, we felt quite safe."

Shortly after the incident on Matipo St, police received another report of a man presenting a firearm toward another person on Riccarton Rd shortly after 3.30pm. No shots were fired.

The man then left in a vehicle. Officers along with the AOS located and arrested the man at an address on Fitzgerald Ave.

The police spokeswoman was unable to confirm if a firearm was located at that incident.