A quick-thinking retired officer in New Jersey jumped into action after seeing a baby girl crying and sweating profusely inside a locked car, as he said the temperature inside the vehicle soared above 120 degrees.

Steve Eckel, 53, used a sledgehammer to smash through the car's front passenger window at a parking lot in Howell on Monday, police said. They told reporters a second good Samaritan, 30-year-old Sarah Mazzone, carried the 4-month-old girl into an air-conditioned store.

“I do believe in guardian angels, and I think that I’m the one for this child,” Eckel told WCBS. “Her hands were out in the car. She was screaming so loud you could see her eyes rolling back.”

Temperatures outside were in the upper 80s.

Investigators determined the mother, 33-year-old Karen Gruen of Lakewood, had left her baby in the car for about 40 minutes. They talked to her after she approached her car in a panic, asking where her baby was, Eckel said.

Police charged her with child endangerment. It's not known if she has a lawyer.

The baby appeared fine after she cooled down, police added.

Eckel, a retired Middlesex County Sheriff’s Office sergeant, told WCBS his instincts as a dad kicked in when he freed the girl from the car. “I almost started to cry; I felt really emotional at that point.”

The Associated Press contributed to this report.