Israel Keyes was arrested Tuesday in Lufkin, Texas, KTRE, a Lufkin radio station, reported. Police said they were able to charge him with kidnapping because of items found in his car.
Samantha Koenig, 18, disappeared Feb. 1. A security camera captured her abduction by an armed man, police said.
Police have said nothing about why Keyes is a suspect, the Anchorage Daily News reported.
"He's the only person we charged, and the only person of interest," Detective Slawomir Markiewicz said. "And the biggest thing at this time is that we haven't found Samantha Koenig and we don't know her whereabouts."
Anchorage police spent hours Tuesday searching the house Keyes shares with Kimberly Anderson. Markiewicz said she is not a suspect.
Police are continuing to assume Koenig is alive and they are investigating an abduction, Markiewicz said.