A Chicago mother ended up in the right place at the right time on Friday evening when she helped rescue two children who were dropped off by a carjacking suspect on the city's Northwest Side.

About 5:12 p.m., a 39-year-old woman was parked at a gas station in the 5900 block of West Montrose Avenue when a male climbed into her vehicle and drove off south on Austin Avenue, Chicago police said.

A 5-year-old girl and a 2-year-old boy were in the back seat of the vehicle at the time, police said.

Officers found the children a couple of blocks away in the 4300 block of North McVicker Avenue in Portage Park, police said. The woman and the children were not injured.

Northwest Side resident Jennifer Villanueva was putting up Halloween decorations with her children when she noticed a speeding car stop near her house.

"I saw this man taking kids out of the car, and they're screaming and crying, then he sped off," Villanueva said.

As soon as the driver sped off, the mother crossed the street and rescued the two young children. Villanueva thought the situation was a custody battle, and didn't realize it was a carjacking until she called police.

She took a further step to comfort the children while they waited for officers to arrive.

"Because I have my own children, I gave them some cookies and juice, and we just waited for police... and were looking at the decorations," Villanueva said.

Villanueva credited the suspect for dropping the children off in a residential area.

"As a parent, and as a teacher, I shudder to think what could've happened if he would've kept going," she said.

No arrests have been reported. Area North detectives are investigating.