The Solano County Sheriff's Office was planning to team up with the Contra Costa County Sheriff's Office Tuesday morning to search for a Fair Oaks man who is presumed to have fallen into the Mare Island Strait, a Vallejo police lieutenant said.

The sheriff's offices will meet with the U.S. Coast Guard at the Vallejo Coast Guard station at 10 a.m., and will search the strait with a sonar video camera, Lt. Kevin Bartlett said.

Philip Steven Mattingly, 77, was working on his tugboat named the "Eugene E" at Berth .10 on the east shore of Mare Island when he was last seen, Vallejo police Lt. Lee Horton said.

The tugboat was anchored alongside the WW2 ship USS LCS 102, Horton said.

Mattingly was last seen around 5 p.m. Saturday. His truck was parked at the scene and his personal items on the boat were still intact, police said.

Mattingly's 52-year-old son called police around 8 a.m. Sunday to report his father was missing. Police do not suspect foul play and are concerned Mattingly's age and health might have contributed to his disappearance, Horton said.

Divers from the Solano County Office of Emergency Services searched the Mare Island Strait, and the Coast Guard searched the shoreline around Mare Island on Sunday.

Office of Emergency Services manager Don Ryan said the dive team was standing by today unless there was evidence of a location where Mattingly might be found.

"The currents were terrible yesterday. We couldn't dive deep down," Ryan said.

The dive team was at the scene for 10 hours Sunday but in the water only two hours, Ryan said.