Watch: Heart-stopping moment hero cop saves choking infant as desperate mum weeps

Dashcam footage has captured the heart-stopping moment a police officer saved a 3-week-old baby from choking as her desperate mum looked on in horror.

Footage shows the moment Michigan officer Cameron Maciejewski managed to revive the tiny infant girl after she choked and lost consciousness.

The baby girl was drinking milk from a bottle when she began to choke and pass out.

Officer Maciejewski rushed to the scene where dashcam shows him grabbing the baby.

"Hey what's going on with the baby?" Maciejewski is heard asking.

He can be heard telling the panicked mother to calm down and asks to see the baby.

"Let me see the baby please. Hold on. He's still blinking. He's blinking," he can be heard telling the hysterical mother

He then grabs the baby and calmly turns her onto her tummy in his arms, giving her back some light taps, successfully clearing her airways.

"There we go! He's crying. He's crying. It's ok. He's crying, so he's ok," the officer is heard saying.

The baby's mum crumples onto the floor in distress and is helped to her feet by her family members.

Heartstopping video footage shows the moment Officer Cameron Maciejewski managed to revive the tiny infant girl after she choked and lost consciousness. Photo / Michigan Police

"Are you ok? She's breathing now. She's okay. She's got a pulse and she's breathing," Maciejewski reassures the mother.

Emergency services can be heard arriving off-camera to check over the baby and authorities learn that the little girl is just 3 weeks old.

Sterling Heights police praised the calm, quick-thinking action of Maciejewski for saving the newborn's life.

"If it wasn't for Officer Maciejewski's quick, calm, lifesaving actions, the outcome of this incident could have been tragically different," they said in a statement.

"Not only did the officer save the baby, but the officer did an outstanding job consoling the family."