One of the women, an 84-year-old, was allegedly assaulted twice over the summer.
Investigators say Arias fondled her sexually and forced her to do the same to him.
The other victim, a 60-year-old, alleges a similar assault.
"This man was placed in a position to take care of people who were unable to take care of themselves, and instead he violated that trust and did probably the worst thing that he could have done and that is to sexually assault these women," said Rick Martinez, Anaheim Police Department.
The alleged assaults happened at the Anaheim Terrace Care Center on South Knott Avenue.
Administrators wouldn't talk on camera, instead they issued a written statement:
"We diligently strive to provide a safe and secure environment for our residents that includes adhering to a 'no tolerance' stance against violations of residents' right as has been alleged in this particular situation. We have in the past worked closely with representatives of the regulatory agency and the local police authorities on this issue, and we will continue to do so in the future as we try to obtain more information on the situation."
Anaheim police officials say the nursing home has been cooperating with investigators, but they are worried there may be other victims.
"We understand that he worked at this facility here in Anaheim for a period of time. We've also come to realize that he's worked at a different facility, but we just don't know where that is," said Martinez.
Now investigators are working to find out more about where he worked. Police say if you have loved ones at local nursing homes, ask them if they had any contact with Arias.
If you have any information that could help investigators with this case, you're urged to call the Anaheim police department at 714-765-1623.
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