A 48-year-old man was severely burned when he fell into a hot spring at Old Faithful Geyser in Yellowstone National Park on Sunday night.

Cade Edmond Siemens told park rangers he plunged into the thermal water after venturing off alone off the boardwalk — which is forbidden among visitors — without a flashlight, according to the National Park Service.

When rangers went to investigate the scene this morning, they discovered the man’s shoe, hat and a beer car near the geyser, NPS said.

Footprints leading to and from the geyser, as well as blood, were also detected.

After the fall, Siemens, an American who’s living in India, went back to his room at the Old Faithful Inn and called for help around midnight.

He was taken to Eastern Idaho Regional Medical Center with severe burns to a significant portion of his body, the NPS said.

Rangers were investigating Monday to determine if Siemen’s fall caused any damage to the geyser cone.

The United State Attorney’s Office will review the findings once the investigation is completed.

Sunday marks the first serious injury at the Old Faithful Geyser thermal area since June 2017, when a man fell into a hot spring in the Lower Geyser Basin.

A year before that, a man died after slipping into a hot spring in Norris Geyser Basin.