The remains of an infant, believed to be those of missing Tucson girl Vanessa Martinez, were found in a shallow desert grave early Tuesday morning.

Search dogs found the body about 6:20 a.m. in a remote desert area northwest of Toltec Road and Interstate 10, north of Tucson.

Pima County Sheriff’s detectives and members of Southern Arizona Rescue Dogs began searching the area about 5 a.m. today.

The infant’s parents, Olivia Paige Martinez, 20, and Jonathan Niles Kesterson, 26, were arrested in San Diego in connection with the death of their daughter, the Pima County Sheriff's Department said Monday.

The Tucson investigation began when Kesterson was arrested April 12 on unrelated charges in California. While in custody in San Diego, Kesterson made comments to corrections officers regarding the death, according to the Pima sheriff’s department.

Pima County sheriff's detectives flew to San Diego to interview Kesterson, and based on the initial interview, arrest warrants were issued for the parents.

Olivia Martinez was returned to Pima County Friday. Kesterson was brought back Monday. Both were being held in the Pima County jail.

No details were released about the cause of the baby’s death. Vanessa was born in October, according to the Sheriff's Department.