A Guelph-area medical clinic operator already accused of sexually assaulting eight of his patients is now facing new charges, including some related to weapons and death threats.

Sherman Lai was first arrested last October, and has had new charges added to the tally against him several times since then.

Guelph police say he is the operator of the Centre of Integrative Natural Medicine in Morriston, which was previously located on Surrey Street in Guelph. The clinic claims to be focused on traditional Chinese medicinal practices.

Prior to last week, Lai had been charged with nine counts of sexual assault involving eight former patients.

Police say three more alleged victims have come forward, resulting in four new sexual assault charges. Additionally, based on their allegations, Lai has been charged with one count of assault, two counts of assault with a weapon, two counts of uttering death threats and two counts of possession of a weapon for a dangerous purpose.

According to police, Lai’s clients included Guelph-area residents and referrals from Toronto and other communities. They want to hear from anyone else who believes they have information that might help investigators.