The guy walked into the convenience store on Almeda Road near Highway 288 on Nov. 19 wearing a brightly-colored floral scarf.
Surveillance video showed him walking around the store, appearing to browse through the aisles. Suddenly, he jumps over the counter and punches the clerk, knocking her to the ground. He tried to stab her several times, according to HPD's Robbery Division, but she was able to stop him by holding his arm.
A customer walked in, saw what was happening and yelled at the suspect to stop while calling the police.
The guy grabbed a bag of cupcakes before he ran out the door.
Along with the scarf, the suspect was wearing a maroon hoodie and black sweatpants. He's about 5 feet 10 inches tall with a thin build, curly hair and a bald spot in the back.
Police want to catch him before someone gets hurt.
If you recognize the man, you're asked to call Crime Stoppers at 713-222-TIPS (8477). You must contact them directly or submit an online tip at crime-stoppers.org to be eligible for a reward up to $5,000.