CHICAGO (CBS) — Kierra Coles vanished from the city’s South Side a year and a day ago Thursday, and police have continued their search for the postal worker – who was pregnant when she disappeared.

As CBS 2’s Jermont Terry reported, investigators believe there is a chance someone can crack the case open.

Coles, then 26, was last seen Oct. 2, 2018 at 81st Street and Vernon Avenue in the Chatham neighborhood, and was three months pregnant at the time.

Kierra Coles was last seen on Oct. 2, 2018, near 81st and Vernon. (Credit: Chicago Police)

The case has left her family – and Chicago Police detectives – stumped.

Coles had called in sick to work the day she disappeared. But surveillance video showed her wearing her U.S. Postal Service uniform, walking up and down the street the morning she vanished.

Her family has said they found her car parked on her block, with her cell phone and purse still inside.

“Someone out there has seen something – they know something. They know what happened to Kierra,” said police Lt. Senora Ben. “And we’re asking and pleading with them for that information.”

Coles’ family and the U.S. Postal Service have offered more than $46,000 in reward money for information leading to her whereabouts.

Anyone with information on Coles’ whereabouts should call Area South detectives at (312) 747-8274.