Tucson police say parents Luis and Andrea Ramirez (bottom right) abducted their  Luis, Jr. (left) and daughter Khamila (top right) during a supervised visit with a child protection worker Friday May 4, 2018

The car a Tucson couple is accused of taking during the abduction of their two children during a supervised visit at a Tucson park has been found in Nogales, near the Arizona-Sonora border, police say.

The couple, the non-custodial parents of the two children, and the kids are still missing, police said.

The 6-month-old-girl and a five-year-old boy were abducted by the couple Friday under the watch of a child protection worker who was threatened with a stun gun then tied to a tree with duct tape, authorities said.

The parents, identified as Luis Ramirez, 30, and his wife Andrea Ramirez, 28, fled with the children in the faded, teal green, 1996, four-door Toyota Camry found in Nogales Saturday.

The couple are accused of abducting son Luis Ramirez, Jr., 5, and daughter Kahmila Ramirez, 6 months, during a supervised visit at Silverlake Park on South Kino Parkway at East Silverlake Road Friday that was overseen by a contract case aide working for the state Department of Child Safety, said Sgt. Pete Dugan of Tucson Police Department.

Dugan said police went to the park about 10:45 a.m. Friday when a passerby noticed the child protection aide bound to a tree and untied her, then called 911. The woman spent more than a half hour tied up before help arrived, Dugan said. 

Police say the father assaulted the woman, threatened her with a Taser and tied her to a tree at the park.

Luis Ramirez is described as being 5-feet 7-inches tall, weighs about 210 pounds, has black hair, brown eyes, and a mustache and beard. Andrea Ramirez is about 5-feet 5-inches tall and weighs about 220 pounds. She has black hair and brown eyes, police say.

When last seen, the father was wearing a red and white striped polo shirt and jeans and the mother wore a white shirt and jeans and had her hair tied into a bun, Dugan said. 

The abducted boy was last seen wearing a gray and white striped polo shirt and khaki shorts, and the baby wore a white Onesie with yellow ruffles, Dugan said. 

On May 2, the couple was arraigned on 20 counts of sexual exploitation of a minor, which did not involve their children. The department is "extremely" concerned for the children's safety due to the couple's actions and charges against them. 

Anyone with information about the family's whereabouts is asked to call 911.