A private Christchurch boys' school was in lockdown after a man threatened staff and made mention of a gun.
The man entered the Christ's College grounds about 9.10am.
Police said they had "received reports" the man had made threats towards school staff.
"As per their emergency procedures, the school went into lockdown and contacted police," they said in a statement.
"Police have responded to the incident and made enquiries into locating the male."
At 10.20am, police located the man and are speaking with him.