TIJUANA, Mexico (AP) — Mexican authorities say they have discovered two more bodies at a house in Tijuana where a couple with dual U.S.-Mexico citizenship were found buried, allegedly by their son-in-law.

The attorney general's office for the state of Baja California, just south of San Diego, California, said late Saturday the second set of bodies —one male and the other female— are in a state of advanced decomposition.

The suspect was deported from the U.S. in 2012 and had been living at a property in Tijuana owned by his in-laws.

Maria Teresa López, 65, and her husband Jesús Rubén López, 70, entered Mexico on January 10 to retrieve the equivalent of $6,400 in rent for apartments they owned in the city, and that their son-in-law had supposedly collected on their behalf.

A daughter reported the couple from Garden Grove, California missing the next day.

Authorities suspect the man killed his in-laws in a dispute over money. They say he confessed to burying them on one of their properties, where he lived. All four bodies were covered in lime.