SAN FRANCISCO (KRON) — A deceased person was found Wednesday afternoon inside a public transportation tunnel in San Francisco, according to San Francisco Police.

Around 3:05 p.m. officers responded to a call from a Muni train operator, and found the body in an inbound tunnel between Castro St. and Church St. stations, police said.

Police and Muni officials are now working to pull video footage of the area and determine what happened.

“This is being investigated as a collision and will be handled by the SFPD Traffic Collision Investigation Unit and the Medical Examiner’s Office,” police said.

The situation has caused major delays in the subway system between the West Portal and Church Street stations, according to a San Francisco Municipal Transportation Agency spokesman.

The SFMTA began reporting delays shortly after 3 p.m. today, and passengers are advised to take alternate routes to their destinations.

Bus shuttles are providing service between West Portal and Van Ness stations, and BART is honoring Muni fares.