DENVER (CBS4) – A Boulder County Sheriff’s deputy whose phone call to police tipped authorities off to what appears to be a severe case of child abuse says he witnessed a “heartbreaking” situation.

Deputy Sean Gwynn was shopping in Lakewood and was off duty on Feb. 2 when he spotted Kenny and Kathleen Sanchez with their 3-year-old daughter. They were also inside the Disabled American Veterans Thrift Store.

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He says the child appeared to be the victim of abuse and he felt he needed to help.

“What I witnessed didn’t feel right at all. This was a defenseless child,” said Gwynn, who called police right away.

Investigators say they then uncovered conduct showing the girl was malnourished and mistreated. Both parents were arrested.

Kenny and Kathleen Sanchez are now each charged with child abuse resulting in serious bodily injury. Police say their daughter weighed only 19 pounds.

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Kathleen and Kenny Sanchez (credit: Denver DA)

“Did it just break your heart to see something like that?” CBS4’s Dominic Garcia asked Gwynn, who said he can only discuss certain elements of the case due to the ongoing investigation.

“It did. I wouldn’t want to see it happen to my kids and I sure wouldn’t want to see it happen to anyone else,” Gwynn said.

Until CBS4 contacted him, Gwynn didn’t know his one call launched the investigation and led to the arrests. He said he wants people to know that’s all it takes.

“If you see something don’t be afraid to report it. We need to protect our children out there,” Gwynn said.

The girl’s brother and sister have been placed in protective care.

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Both defendants remain in custody at the Denver County Jail on bonds of $50,000 each. They are scheduled to appear in court Feb. 16 to be advised of the charges.