A 20-year-old man has been arrested following an incident outside a high school in Rexton on Friday that resulted in a lockdown.

Police received a report that a man with a gun was seen just outside Bonar Law Memorial School at around 8:30 a.m., RCMP Sgt. Jeff Johnston stated in a news release.

The gun has since been deemed a fake, said Johnston, describing it as a handgun style pellet gun.

But as a precaution, the school was immediately locked down by officials, he said.

The man, who is not currently a student at the school, never entered the building and was arrested without incident a short time later, said Johnston.

The investigation continues.

Meanwhile, classes were back on schedule by the afternoon, said Anglophone North School District Superintendent Nancy Boucher.

But school officials are concerned about the effect of the incident on students, she said.

"I imagine a couple of students could be quite upset by today's events. It's not a typical happening for a high school, that's for sure, but we're monitoring them closely."

Bonar Law Memorial has about 370 students from Rexton and the surrounding communities.

A remand hearing for the suspect will be held by telephone on Saturday, police said.