A Townsville mum has recounted the “most terrifying experience” of her life when  thieves stole her vehicle with her two-month-old baby sleeping inside.

Sarah (surname withheld) was cleaning out her Isuzu D-max in her driveway in Garbutt on Monday afternoon, with the child in a car seat.

Thieves took the opportunity to jump into the vehicle and drive away, with footage showing Sarah running after it.

The distraught mum cried “Help, help, my boy is inside” as the SUV was driven off around 1.44pm.

Two minutes later, the thieves returned and placed the baby still in its car seat on the curb, also handing Sarah back her phone.

She asked them why they had committed such a crime and they reportedly replied: “We’re just bad guys”.

Police said no one was physically injured during the incident, and the baby was assessed by paramedics as a precaution.

Police arrived a short time later and conducted patrols. The vehicle was found abandoned later.

Sarah told 7NEWS it felt like a lifetime as she watched her baby disappear.

“My soul left my body. It was the most terrifying thing that has probably ever happened in my life, that I’ll probably ever experience,” she told 7NEWS.

Investigators are appealing for anyone who has seen or has vision of the black Isuzu D-Max with Queensland registration 840A4B to contact police.

Investigations are ongoing.