05/02/2013 04:15 EDT | Updated 07/02/2013 05:12 EDT

Surrey Six investigator quits as more charges laid

An RCMP officer facing charges in connection with a high-profile murder investigation in Surrey, B.C., has quit the force as the Crown approves another criminal charge against him.

Former sgt. Derek Brassington has been charged with theft under $5,000 in an incident alleged to have taken place in Burnaby, B.C., on March 30.

Brassington is one of four officers already facing charges, including breach of trust, obstruction of justice and fraud, dating back to their handling of the Surrey Six slayings, a 2007 gangland slaying that left six dead in a Surrey highrise.

The investigation into the officers began with allegations Brassington had a relationship and impregnated a woman who was a potential witness in the case and a former girlfriend of two of those charged in the murders.

- RCMP charged in B.C. murder probe

- RCMP officer's alleged girlfriend pregnant, say sources

Brassington has already been subject to internal Code of Conduct reviews and the RCMP had been pushing for his removal from the force.

He will make his first appearance in provincial court on May 7.