A 23-year-old Kansas mother and her two young children are missing, and authorities are asking the public for help locating them.

According to a Facebook post from the Kansas Bureau of Investigation (KBI), Martha Unger and her daughters — Madilynn Grace Unger, 2, and Haylie Faith Unger, 1 — were last seen on Friday, June 28.

They were reported missing from their home in rural Haskell County before 7 p.m. local time on Friday, and the state bureau said that Martha “may have been coerced to travel to Mexico to a religious rehabilitation facility” with another couple in their 50s.

According to KBI, Martha was driving a 2015 white Ford Explorer with a Kansas tag, and may have joined Corney and Elizabeth Klaasen, who were driving a white and black Chevy Blazer with a Mexico tag.

“Investigators wish to check the welfare of Martha and her children. If you see the subjects or vehicles connected to this endangered persons advisory, call 911 immediately,” KBI said in its Facebook post, asking those with any information to call the Haskell County Sheriff’s Office.

Corney is described as a 6’2 male weighing about 200 lbs. He is “clean shaven and last known to be wearing jeans and a button-up shirt,” KBI said. The Unger children have blonde hair and blue eyes, while Martha is 5’6 and weighs around 120 pounds. She has brown hair and green eyes.

The Haskell County Sheriff’s Office did not immediately respond to PEOPLE’s request for more information on Sunday.

According to KBI, which is the “central repository of information relating to missing and unidentified persons,” 420 adults and 261 children are currently missing in the state of Kansas.

The bureau’s website encourages those who notice that someone is missing to “immediately report the person as missing to your local law enforcement agency” and “limit access to the home where the person resides, their vehicle and electronic devices.”

“Do not wait, especially if the missing person is vulnerable; notify police as soon as you think something is wrong,” KBI said.