They called police after the incident, which happened around 3:00 p.m. Wednesday on the 4300 block of South Lowell Boulevard in Sheridan.
The victim's mother, Desiree Gonzales, said she was upstairs in her apartment when the incident happened.
She said her 4-year-old son left the front door open, which allowed the toddler to escape.
The 2 year old nearly made it to the street when she says a woman scooped him up.
Gonzales yelled and the suspect dropped the boy and took off in a white van.
"She just turned around and dropped my son on the floor like a sack of potatoes, like just dropped him,"Gonzales said.
"All I could see was the edge of her foot getting in the van. I'm still shaky; my heart's still racing; my hands have not stopped shaking since this happened," she added.
Police are looking for an Asian woman, about 30-years-old, 5-feet-5-inches tall, 120 pounds with dark shoulder-length hair.
Police say someone else was driving the van, which is described as an older white van with paneling, two rear doors with windows with rust on the bottom of the van doors.
Anyone with information about either the suspects or the van is asked to call Crime Stoppers - at 720-913-STOP.
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