Agustin Armaraz Espinoza, 55, and Marisela Gomez Espinosa, 53.

Agustin Armaraz Espinoza, 55, and Marisela Gomez Espinosa, 53. (Santa Ana PD/ DMV photo)

SANTA ANA -- An Orange County man has been arrested on suspicion of beating his wife to death inside their Santa Ana home.

Agustin Armaraz Espinoza, 55, was detained at the U.S.- Mexico border Thursday when he was coming back from Mexico, according to Cpl. Anthony Bertagna of the Santa Ana Police Department.

53-year-old Marisela Gomez Espinoza was found dead in a bedroom of their home in the 2400 block of North Wright Street on Friday, after co-workers notified police she'd been missing for two days.

Detectives tried to contact her husband, but couldn't find him. They became concerned he might also have been a victim, and put his license plate in a law enforcement database.

That's what lead to him being stopped at the border by U.S. Customs officers.

Police brought Espinoza in for questioning "person of interest," then arrested him after the interview, according to Bertagna.

Bertagna said there was enough cause to arrest Espinoza for homicide, adding that detectives think this is a case of domestic violence.

Friends and family told police the couple was planning to divorce, but hadn't filed papers yet.

Marisela Espinoza was last seen Tuesday afternoon leaving her job at Alcoa Fastening Systems in Fullerton.

An autopsy performed Friday revealed she died of blunt force trauma to the head, Bertagna said.