HOUSTON -- Houston police are searching for a local doctor who has been missing for more than three days, KPRC Local 2 reported Sunday.

Dr. Melinda Superville, 43, was last seen leaving her chiropractic office on Antoine Drive near Hempstead Highway in northwest Houston on Friday.

Superville's husband, Thomas, found her keys hanging from the front door of her office hours later and believes she might have been abducted while walking to her home a block away.

"I should have heard from her by now. It's not in her nature, something has happened to her, and the only thing I can think is somebody has abducted her," Thomas Superville told KPRC Local 2. "She's my world. I've asked everybody I can, 'What do you do?' Nobody has any answers."

The Supervilles have a 2-year-old son, Tommy, who still does not know his mother is missing.

"At this point, luckily he hasn't realized that mommy is not there," Thomas Superville said.

Thomas Superville said his wife left her purse at home Friday morning and that she doesn't have any credit cards or a cell phone with her.

Anyone with information should call the Houston Police Department's Missing Persons Unit at (713) 731-5223.