A former Pinole police commander was arrested Friday and his wife was at large and wanted following a months-long investigation into an elder abuse case, authorities said.

Matthew Messier, 36, was arrested by Alameda County Adult Protective Services on behalf of an 82-year-old Pleasanton man, said Pleasanton Police Sgt. Kurt Schlehuber.

Messier, a Pleasanton resident, and his wife Elizabeth Regulado, 30, allegedly used his position of authority to gain the elderly victim's trust and then placed the man's entire estate into a trust only they controlled, Schlehuber said.

Messier was employed by Pinole police at the time the incident was reported.

He was arrested on a warrant on suspicion of grand theft, three counts of attempted grand theft, four counts of elder abuse, forgery, two counts of registering a stolen document, criminal conspiracy and practicing law without a license, police said.

Regulado is wanted for one count of criminal conspiracy.

Anyone with information on Regulado's whereabouts or information about this case should contact Pleasanton police at (925) 931-5100 and reference case 12-26567.