St. Paul firefighters rescued two teenagers who got trapped while exploring caves on the city's West Side early Saturday.

The boys descended 100 feet onto a cliff area of the bluffs around 1:30 a.m. and were unable to return to their entry point.

A third teen, who at the last minute decided to stay behind, called 911 for help. Firefighters located an access point that "was too narrow for a grown man to get down," authorities said. The rescue took 2½ hours. No one was injured.

"Accessing these caves is very dangerous and illegal," Acting Fire Chief Matt Simpson wrote in a statement. "It is extremely fortunate in this case that the friend, who chose not to descend in to the cave with the others, made the correct decision to call 911 for help when he did and allowed the professionals with the training, knowledge, and experience necessary to rescue these young men perform their duties."

Authorities are working with the St. Paul Parks and Recreation department to secure the caves.