Authorities report finding a body in the in-bound Muni tunnel between Church and Castro stations, halting service between Church and West Portal stations this afternoon.

Around 4pm Wednesday, tipster Ed Lawrence H. alerted us that Muni was experiencing delays at West Portal Station. "Current at West Portal Station and no IB trains are moving," he wrote.

The SFPD has confirmed that a Muni train operator reported seeing a person in the tunnel. SFPD responded at 3:05pm and located the body of a deceased person in the in-bound tunnel, just east of Castro Street Station, between the Castro and Church Street stations.

"This is being investigated as a collision and will be handled by the SFPD Traffic Collision Investigation Unit and the Medical Examiner's Office," the SFPD spokesperson said.

The SFMTA confirmed that shuttles are operating between West Portal and Church Station, but also encouraged commuters to seek alternative transportation due to ongoing delays.

UPDATE: Ltd #KIngleside, #MOceanview, and #LTaraval svc going OB via WP. Still consider using alternative routes, shuttles and @SFBART.

— SFMTA (@sfmta_muni) January 12, 2017

UPDATE: #subwaysvc delayed btwn WP and Church due to a medical emergency at Church Station. Shuttles to support from Church to WP.

— SFMTA (@sfmta_muni) January 11, 2017

Castro Muni Station closed. Medical emergency. Medical Examiner on scene. pic.twitter.com/rgCiisEQjL

— Steven Bracco (@Braccs) January 12, 2017

Update, 10:50am 1/12: On Twitter and Hoodline's Facebook page, a witness has offered additional information on the events leading up to the victim's possible cause of death.

In a series of tweets directed at the SFMTA, Twitter user Damaged Youth says that he and the victim were riding an inbound train, in the second car, when he saw the victim exit into Castro station. He says he then saw the victim approach the second car's vacant "driver compartment" and reach his head and waist through the window, feet in the air out the window, in an attempt to take transfer tickets.

The train began moving, the witness states, and "as we passed the orange metal gate preventing pedestrians from walking into the tunnel the lower half of his body crashed into that metal gate. He held on maybe two seconds longer before he rolled out of the window."

While the SFPD confirmed yesterday that officers responded to the scene at 3:05pm, the witness noted on Hoodline's Facebook page that he originally reported this incident to authorities at 11:25am. On Twitter, he elaborates that he knew there was another train right behind theirs, jumped up and ran to the first car to alert the train operator, who then reported the details to central dispatch.

As of 9am this morning, the SFPD has only confirmed, "A body was located inside the Muni tunnel by Castro station. Cause of death undetermined at this time."

We'll share more information on the investigation as we learn more.

Thanks to tipster Ed Lawrence H. for the tip.

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