On May 1, 2016 dispatchers in Corpus Christi, TX received a disturbing call, and four young children, ages 4-9, were brought to the hospital. Doctors found all were victims of extreme sexual abuse. Their mother had found out that the children's father was allegedly molesting and raping them, telling authorities she caught him behind a closed door.

When the children's mother confronted the man she thought was loving and leading their family, Martin Munoz, he was apologetic. They drove around and the mother said she left him at a local grocery store and drove directly home to be with her girls. She said Lucy Viallareal, Martin's mother, was supposed to pick him up, but it's unclear where she was taking him.

Investigators said DNA evidence confirmed the horrific abuse the children endured and claimed that this was the worst case of abuse they've seen in their careers.

As for Martin, authorities learned he generally spent the most time with the girls, while their mother worked all the time. A neighbor told "In Pursuit with John Walsh," that while Martin was well spoken and very polite, he had complete control over the children.

As the search to find Martin intensified, US Marshals said they received word Munoz was south of the border in Mexico with another fugitive out of Macon, GA. The second fugitive is an older man named Marcelo Gomez. On the same day the mother of the girls discovered the horrific abuse, US Marshals said they found evidence Viallareal, the little girl's grandmother, crossed into Mexico with her son in a car. It seemed Villareal attempted to protect her son, helping him to get further away, allegedly, before protecting her own grandchildren.

As for Gomez, US Marshals said he allegedly killed a police officer's son on August 7, 1997. Michael Todd Stewart was involved in a deadly accident while he was on his way to work on his motorcycle. A pick up truck pulled out in front of him, and he struck the truck on his motorcycle. The truck fled the scene.

Host Callahan Walsh called Gomez a "professional fugitive." He's been on the run for more than 20 years and he knew Munoz prior to the crimes he's accused of. Gomez was previously part of Munoz's family and at one point he even helped to raise him since he was 9-years-old.

As for Munoz he's facing a number of charges including 17 counts of aggravated sexual assault of a child and two counts of impeding breath and circulation.

Gomez was also part of a local biker club called the Calavares, and it's possible they are helping to hide Munoz. As for Munoz, he did not speak Spanish when he went on the run in 2016, but that may have changed now. US Marshals believe it's possible Gomez does not understand exactly what type of abuse Munoz is wanted for who is described by Marshals as a sexual predator.

John Walsh said, "Martin Munoz is one of the most twisted human beings I've ever hunted and he's at the top of my personal most wanted list. You know, there's a special place in hell for anyone who could molest a child, especially if it's your own flesh and blood, that's the ultimate betrayal."

If you know where either one of these fugitives are hiding out, please contact our hotline. Host John Walsh guarantees you can remain anonymous: 833-378-7783 (3-PURSUE).

Martin Munoz

HEIGHT: 5 feet 6 inches tall

WEIGHT: 185 pounds

HAIR: Brown

EYES: Brown

SEX: Hispanic Male

DOB: September 7, 1988

LOCATION OF CRIME: Corpus Christi, TX

CONNECTIONS TO: Mexico

CHARGES: 17 counts of aggravated sexual assault of a child (among other charges)

CHARACTERISTICS: Munoz's stepfather was a member of a local biker club, the Calavares. Allegedly smokes marijuana and is known to drink Jagermeister. Possible small dark mole / freckle on the front of his neck. Has a tattoo on his chest (unclear which side).