OCEAN CITY, Md. (AP) — Maryland authorities are investigating a diving accident in Ocean City that left a Pennsylvania man critically injured.

Maryland Natural Resources Police say it occurred shortly before 6 p.m. Tuesday night as a group was returning a pontoon boat to a rental facility after visiting Seacrets bar.

Authorities say 23-year-old Kiefer Kuhn of Dover, Pennsylvania, dove head first from the slow-moving boat into very shallow waters of Isle of Wight Bay.

Kuhn’s friends pulled him from the water, and he was taken to Shock Trauma hospital in Baltimore with an apparent spinal injury. Hospital spokeswoman Cindy Rivers said he was in critical condition Wednesday.

Authorities are awaiting results of toxicology tests on two people who reportedly had operated the rental boat.

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