Police investigating an Armadale man following an alleged sex attack of a 19-year-old man on January 21 have discovered 20 video recordings suggesting there may potentially be multiple victims.

On Tuesday Nine News Perth reported that police believe a predator has been targeting young men in Claremont nightclubs and possibly in the Perth CBD.

WA police are investigating the incident. Credit:File Image

Crime reporter Jerrie Demasi said police only found the alleged attacker because the 19-year-old man woke up during an incident.

"He was ... allegedly drugged, abducted and sexually assaulted," Ms Demasi said.