The Sonoma County Coroner's Office is in contact with the family of a person who went missing 21 years ago in an effort to identify skeletal remains found recently at the bottom of Lake Sonoma, Sheriff's Sgt. Greg Stashyn said Thursday.

The remains were recovered by an FBI dive team on Feb. 4 and 5 after a recreational diver spotted them on Dec. 9. The FBI team had to be called in because of depth and complexity of the task — the remains were found in about 100 feet of water.

Based on where the bones were discovered, the Coroner's Office believes they belong to a person whose vehicle was found parked on the bridge 21 years ago, engine running, Stashyn said.

The person was never found and it is presumed he or she committed suicide by jumping off the bridge, Stashyn said. The Coroner's office is working closely with the missing person's family to confirm the identification, he said. That includes checking dental records, if they can be found, or comparing DNA.

"We're still putting it all together," Stashyn said.

The missing person's name, gender and city of residence will not be released until the remains are identified, Stashyn said.