EL PASO, Texas -- KFOX obtained the arrest affidavit of David Marmolejo. He is charged with murder in the death of his mother, Gloria Marmolejo.

David Marmolejo was arrested and charged with strangling his mother then dumping her body in the desert near Santa Teresa, N.M.

The arrest affidavit claims David Marmolejo was having a romantic relationship with his stepsister, and his mother returned to El Paso from Phoenix, Ariz., to try and stop it.

It also states police found a number of inconsistencies in David Marmolejo 's sworn statement. While cell phone towers placed him close to the area where his mother's body was found, later in the week, a witness reported seeing David Marmolejo in Santa Teresa before his mother's body was discovered apparently crying and praying.