Mounties are investigating after a man reportedly exposed his genitals to a group of students at a middle school in Courtenay.

A group of students were outside of Lake Trail School at around 1 p.m. Monday when a man described as being in his early 20s walked through school grounds.

The man had his pants open and genitals exposed, according to RCMP, prompting students to notify school staff who then contacted police.

He's described as a white man between 20 and 30 years old, wearing a grey sweater with a white T-shirt underneath, jeans or dark pants and a grey or blue hat.

A witness told police that the man looked unkempt or disheveled. Police say the group of girls present for the incident did the right thing by immediately telling an adult.

"They ran away from the vehicle and they went and told a trusted adult," said Comox Valley RCMP spokekswoman Const. Monika Terragni. "This is a good opportunity to talk with any children in your care about stranger danger, and about getting out of uncomfortable situations and talking about them with adults."

Mounties are asking anyone with information on the incident to contact them at 250-338-1321 and quote file number 2018-15063, or call Crime Stoppers at 1-800-222-8477.