Police have seized a water pistol and spoken to a 16-year-old girl after a TAFE campus was put in lockdown over reports of suspicious behaviour.

Officers had been going classroom to classroom and building to building at the Campbelltown TAFE after security alerted them to two people seen acting suspiciously about 4.30pm today.

“Police attended the campus and reviewed CCTV holdings and commenced inquiries into the whereabouts of the two people,” NSW Police said.

“Police completed a sweep of all classrooms and buildings within the campus, with no items of interest located.”

About 7pm, officers went to a Campbelltown home where police said they spoke with a 16-year-old girl.

“As part of those inquiries, police seized a water pistol,” police said.

“Investigations continue.”

The campus remains in lockdown.The campus was put into lockdown. (Nine)

Earlier there were reports that someone had been spotted holding what was believed to be a firearm.

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