From left, composite sketches from attacks in Surrey in 2009, Delta in 2007 and Vancouver in 1995. ((RCMP))

Police in Surrey, B.C., say they have linked the suspect in a recent sexual assault on a six-year-old girl to attacks that occurred in other areas of Metro Vancouver.

The most recent attack happened on July 3 in the area of 139th Street and 62nd Avenue. The girl was walking with her 12-year-old brother and his friend when a man with a knife threatened the boys, separated them from the girl and assaulted her.

Sgt. Roger Morrow of the Surrey RCMP said DNA evidence links the suspect to an attack on two 14-year-old girls in Delta in 2007, and an attack on a 13-year-old girl in Vancouver in 1995.

Morrow said in all three assaults, the suspect either brandished or threatened the use of a knife. He said composite drawings from the three cases also show similarities.

Witnesses have described the man as dark-skinned — possibly South Asian or Hispanic — between 20 and 30 years of age, about five-foot-ten-inches tall, with short, dark hair and dark eyes.

An updated tip line has been set up to gather information on the case. Anyone with information is asked to call 604-507-8066.