Mexican authorities have made an arrest in the killing of a Canadian tourist at a popular beach resort.

Omar Barajas, the state police commander, said Monday that investigators determined an American man gave police a false statement about what he saw the night B.C. native Bouabal Bounthavorn was shot to death.

Barajas said Michael Thompson, 32, initially told police he saw an unknown man argue with and shoot the 29-year-old Canadian tourist in his hotel room in Cabo San Lucas on May 15.

Bounthavorn's 24-year-old girlfriend was shot in the ankle and survived the attack.

Officials now believe Thompson knew the killer, Barajas alleged.

Thompson, who has been held as a witness since the shooting, has been charged with giving a false statement to investigators.

Police have also detained a Mexican man but Barajas wouldn't say why and would not comment on a possible motive for the killing.

With files from The Associated Press