Honolulu firefighters responded Thursday morning to an injured man in Kipapa Gulch who suffered severe injuries consistent with a fall from about 50 feet.

Shortly after 6 a.m. a bystander heard the man call for help. Honolulu fire spokesman Capt. David Jenkins said the bystander located the man, described as being in his 40s, in the gulch.

Firefighters found the man by 7 a.m. and airlifted him to a landing zone at 10 Acre Park in Mililani. Paramedics took him in serious condition to a hospital.

Jenkins said it’s unclear how the man was injured.