It was a normal Monday for a Washington state mother, until she said two people claiming to work for Child Protective Services (CPS) showed up at her home and tried to take her 4-year-old son into protective custody. But, the CPS said it doesn't have open cases involving the mother — and she claims that they were actually strangers trying to "snatch" her child in broad daylight.

Jessi McCombs said a man and a woman arrived at her home in Marysville, Washington, on Monday. "[She] said she was with CPS and that she was there about my son's injuries and that they were to take him into protective custody," McCombs said, according to CBS Seattle, Washington, affiliate KIRO-TV.

However, she told the station her son doesn't have injuries and McCombs was sure the imposters were mistaken.

Get Breaking News Delivered to Your Inbox

"[I] thought for sure she had the wrong house until she told me his name and birthday," McCombs recounted, according to KIRO-TV. "I asked her, 'Can you show me some identification? Can you show me this order that you supposedly have?' She refused to show me that."

While the two people were dressed in professional clothing, the woman's refusal to produce any type of credentials set off red flags for McCombs.

Jessi McCombs and her son. KIRO-TV

"These people were potentially trying to just snatch my kid, so I started panicking," McCombs said. She told KIRO-TV she pretended to phone 911 — which scared the two off. "She said, 'We'll come back later,' and they left in a hurry down the stairs," recounted the McCombs.

The mother said she doesn't understand why the pair would allegedly pose as CPS workers to attempt to take her son.

Child Protective Services doesn't have any open case involving the Marysville mother, a spokesperson for The Washington State Department of Children, Youth and Families (DCYF) told KIRO-TV. The department told the outlet that legitimate DCYF staff must carry identification.

"In situations where a child must be removed from their home, DCYF staff are accompanied by law enforcement. DCYF staff always carry agency identification and cannot remove a child from their home without a court order signed by a judge or by law enforcement taking a child into custody per RCW 26.44.050," said the department in a statement, according to KIRO-TV.

Marysville police confirmed to KIRO-TV it's investigating the alleged encounter, which took place early Monday. Police have not received any other reports of fake CPS staff reportedly attempting to steal children in the city, but did offer advice to parents in situations such as this one.

"Before allowing any unknown individual into your home, it's always a good idea to check for photo identification," a police department spokesperson told KIRO-TV. "If in doubt, call the office of who they are saying they represent and ask for confirmation. If your still not satisfied call 911 or the non-emergency number and ask for an officer to come out and check credentials."

Jessi McCombs has not yet responded to CBS News' request for comment.