FREMONT, Calif. (KGO) -- Fremont police say a man sexually assaulted a woman who was doing pushups at a 24 Hour Fitness Monday night.
Jonathan Anderson, 33, is a transient out of Fremont, authorities said.
Investigators believe there might be other possible victims and are asking them to come forward.
Police said Anderson confessed to the crime during questioning. Anderson is facing three felony counts of battery and assault and is scheduled to be arraigned in court Thursday afternoon.
A Good Samaritan who heard the victim's screams helped pull the suspect off then held him down until police arrived.
Several 24 Hour Fitness members ABC7 News spoke to wondered what more can be done to secure the gym. ABC7 went into the gym and saw a fingerprint reader and a pin code verification system at the front desk check-in of the facility. Anderson presumably bypassed that security as he entered the gym to make his attack.
"When the guy is not at the desk - maybe he's out for a short break that's when they don't do it (fingerprint scan), but otherwise they do it" said Venkata Nyshedhan, a regular at the gym.
Another gym member, Christine Wilson, is wondering what more can be done to keep those who don't belong at the gym out. "Sometimes when you go in there's nobody there. A card thing might be better on the door or something."
24 Hour Fitness released the following statement to ABC7 News: "We are aware of the incident that occurred recently in our 24 Hour Fitness Paseo Padre club located at 39300 Paseo Padre Parkway in Fremont. We are grateful for the brave club and team members who were able to intervene and detain the individual accused of assaulting another individual in the club. We are working with the Fremont Police Department and as this is an active investigation, we are referring all inquiries to them. We ask anyone who has information on this or other similar incidents involving this suspect to contact Fremont Police Department at (510) 790-6954."
Anyone with information about this incident is asked to please call the Fremont Police Department's Investigative Unit at 510-790-6954 or send an anonymous tip by texting TIP FREMONTPD followed by your message to 888-777.
Woman sexually assaulted at 24 Hour Fitness in Fremont, suspect arrested, police say