Pleasant Grove High School in Utah was locked down on Friday (AEDT), amid claims a student was inside with a gun.

The Salt Lake Tribune reported that the police received an unconfirmed message of threat and had gone to the school to respond to the situation.

Some 30 minutes after the lockdown was confirmed by the Pleasant Grove Police Department, PGPD said students had been released and the lockdown was over.

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Police searched the school room by room after a report came from a student claiming another pupil had a gun.

There were no reports of shots fired or any injuries suffered.

“The lockdown has been lifted,” the PGPD Facebook post said.

“We appreciate the support and patience of all those involved in this incident.”

Earlier, the PGPD confirmed the school was in lock down via its Facebook page.

“Pleasant Grove High School is currently under lock down. We do not have any further information at this time, but will give updates as we receive them. Please do not contact dispatch to ask for updates.”

Parents of the more than 2,000 students were notified and students were to be taken home via bus once they could be safely released.

“Police are on scene and conducting a room by room sweep before students will be released. All students are safe!” the Alpine School District posted on their Facebook page at about 3 pm.

Shaun Wadley, a parent of a student who was in the school told of a text message describing what had occurred.

“She sent me some text messages, she said she’s on lockdown and that she’s really scared,” Mr Wadley told Fox 13 News.

He said his daughter sent the messages from a classroom.

“All together scary,” he said.

“It’s no good, man, we need more gun control … I am concerned, you know, any parent would be with all this response going on.

“Like I said earlier, hopefully it’s a wild-goose chase and it’s a BB gun or a paintball gun, you know, we only know what we’ve been told so far … everyone, as you can see, is on edge.”

The reports came a day after 14 people were killed in a shooting massacre at a social services centre in San Bernardino, California.

– More to come