Police are warning residents in Summerside to shelter in place as they search for a potentially armed and dangerous individual in the city.

An emergency alert issued Wednesday morning identified the suspect as Mitchell Lannigan, a 28-year-old white male who is believed to be on foot in the Water Street East area. The alert says he is believed to be "armed and dangerous."

Lannigan is described as having brown hair and brown eyes, with a medium build. He is approximately five feet eight inches tall…