Minutes after learning that police in Pennsylvania were searching for an SUV as part of a child abduction case, a man spotted the vehicle and called police, leading authorities to a man accused of kidnapping his infant daughter and killing her mother, according to a report.

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Authorities took Antonio Velasquez-Rupert, 36, into custody Saturday within minutes of getting a call from security guard Daniel Derturck, WFMZ reported.

"We're trained to respond on anything and everything that we see, and my training kicked in," Derturck said.

He told the news station he spotted a dark green Ford Explorer described in an Amber Alert released by Pennsylvania State Police at a stop sign in Reading. The city is about 300 miles northwest of Sharpsville, the city from which the infant girl vanished.

"They stopped real (quickly), then just slowly eased around the corner," Derturck told WFMZ.

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Derturck told the news station he followed the vehicle but eventually lost sight of it. Still, he told 911 dispatchers what he saw, and authorities soon after arrested Velasquez-Rupert.

Pennsylvania State Police on Saturday issued an Amber Alert in its search for the man and his 8-month-old daughter. The girl went missing around noon that day. Police found the child's mother, Amanda Downs, dead inside her Sharpsville apartment.

Police found the child healthy and arrested Velasquez-Rupert around 3:45 p.m. Saturday.

"I'm just glad I was an adult that responded to help them get home safe, wherever home is," Deturck told WFMZ. "I just hope that people everywhere across the country can use me as an example, that there is a shining light worth standing up for ... to do the right thing."

Velazquez-Rupert was charged with homicide, kidnapping and custodial interference. He remained in the Berks County Jail Tuesday afternoon.