ST. PAUL — Firefighters rescued a 19-year-old from deep inside a cave along the Mississippi River bluffs early Sunday in St. Paul after he texted a friend that he was trapped before his phone went dead.

Authorities got word around 12:45 a.m. that the teen had fallen into the cave. Firefighters from the St. Paul and Minneapolis advanced tactical-rescue teams brought him to safety around 5 a.m., St. Paul Fire Marshal Steve Zaccard said.

He was pale and shaken but could walk and talk, Zaccard said. He was taken to Regions Hospital with minor injuries. Firefighters searched the entire cave until about 8 a.m. to be sure no one else was trapped inside.

The cave is in Lilydale Regional Park, west of the High Bridge and about 200 feet up from the street below.

The teen fell about 20 feet down a shaft and was roughly 300 feet into the cave, Zaccard said. The cave is “vertical for a while and then curves about 60 degrees to the horizontal and then back several hundred feet,” he said.

“Imagine this at night,” Zaccard said. “You see the vegetation and the steep cliff. This was pitch-black for most of the time we’ve been here.”

Firefighters used maps from the parks department to pinpoint the cave’s opening, Zaccard said. Using ropes and harnesses, “a rescuer went down in the opening and was able to make verbal contact with him, so then came the arduous task of extricating him from there,” the fire marshal said.

The teen, whom firefighters didn’t identify, told his parents he was going to the caves, Zaccard said. He said the teen had been at the cave with friends, but they left or became separated somehow.

There had been a campfire in the cave, leaving smoke and elevated levels of carbon monoxide, Zaccard said.

“That’s one of the things that makes these caves so dangerous and deadly is they have campfires, and then the lack of oxygen creates a lot of carbon monoxide,” he said. “Carbon monoxide is the silent killer. It’s odorless, colorless. Oftentimes, by the time you realize you’re being affected it’s too late for you to do anything about it.”

Five teens have died in St. Paul caves in the past 22 years, Zaccard said. Three died in 2004 and two in 1992, all overcome by carbon monoxide.