"He was just looking suspicious -- running around and running real fast," says an eyewitness.
Investigators tell KSLA News 12 it was just after noon at Mall St. Vincent when the thief acted like he wanted to buy both rings from Lee Michael's Jewelers.
They say when he got his hands on them, he took off.
Detectives say it was only a matter of moments before they had officers surround the perimeter of the parking lot at Mall St. Vincent.
Despite the heavy police presence, the robber was able to get away with the two rings valued at $72,000.
A thief on the run doesn't sit well with shoppers.
"Terrible, cause you never know what they might do to you," says an eyewitness.
Workers at the jewelry store say it's been nearly two and a half years since the last time someone robbed them.
"Unfortunately in the jewelry industry it's always something we're at risk of...yeah...it's pretty sad," says assistant manager Danielle Marcum.
Marcum says it all happened quickly.
Detectives say the man kept a low profile.
Now they'll have to use the descriptions from key witnesses to try and crack the case.
Story By Ben Wolf