A reportedly mentally ill man was taken into custody yesterday by the Cambridge Police Department after leaving a note that suggested he planned to kill himself by jumping in front of a bus.

He was apprehended on JFK Street around 2:45 p.m. and taken to a hospital, according to Cambridge Police spokesperson Daniel M. Riviello.

The Harvard University Police Department issued an advisory to Harvard University Transportation Services and the Massachusetts Bay Transportation Authority to be on the lookout for a 46-year-old man who was last seen near the shopping area around the Harvard Coop.

The man was described as wearing a blue jacket and carrying a green duffel bag.

Around 2:40 p.m., police issued an advisory with that description to all Harvard shuttle drivers, according to General Manager of the Harvard University Transportation Services David E. Harris Jr.

“Apparently the person had a mental illness, and we were issued an advisory,” Harris said.

Emergency police advisories such as these are not typical for Harvard University Transportation Services, according to Harris.

“This was the first time in the 12 years that I’ve been here that we have had an advisory like this,” Harris said. “We usually issue safety advisories for traffic or weather advisories.”

The shuttles were not delayed due to the advisory, and the man was apprehended before any harm occurred around five minutes after the notice was delivered to Harvard drivers.

Cambridge police has not released the name of the individual.

—Staff writer Kerry M. Flynn can be reached at kflynn@college.harvard.edu.