07/30/2012 08:41 pm ET Updated Jul 30, 2012

Bay Area Sex Workers Targeted In String Of Robberies

A crime ring may be targeting prostitutes and other sex workers in the Bay Area.

According to the San Mateo District Attorney's office, a recent home-invasion robbery against a woman may be just the latest in a string of targeted robberies.

At about 6 a.m. on July 11, a witness was sitting in his car before leaving for work when he saw a woman wearing nothing but a t-shirt exit an apartment building with her hands bound with zip ties behind her back.

When the witness approached the woman, she begged him not to call the police, asking him to call another phone number instead. Despite her protests, the witness called the police, launching an investigation into the incident.

The next day, officers arrested Jantar "Kelly" Phun who was in a vehicle parked near the apartment. Inside, they found items belonging to the victim, as well as a gun, a replica, zip ties, bolt cutters and a police scanner. The arrest then led police to two other suspects, Phun's boyfriend Samay Tow Pomsouvanh and Eddie Chi Wei Cheung. All three are facing multiple felony charges.

"Though this was the only related robbery we've seen in our office, we learned from law enforcement that this was not an isolated incident," said Chief Criminal Deputy Karen Guidotti of the District Attorney's office to The Huffington Post.

Phun was also arrested in 2007 for holding up a massage parlor in San Rafael. Her partner in the 2007 crime was arrested in 2010 and sentenced to more than 13 years in prison for a string of similar incidents.

Phun and her associates may be targeting sex workers because they are less likely to report the crimes.

"I can't make any assumptions based on this case, but I know from a common sense standpoint that people who are sex workers are very unlikely to call the police," said Guidotti. "That makes them so much more vulnerable."