Early Sunday morning a team of thieves pried open the office door of an accounting and income tax service.
Investigators say after the thieves got inside the accounting office, they cut through a wall that separated the service from Harold's Jewelry.
The hole lined up exactly with the jeweler's safe.
The thieves then used commercial metal cutters to peel open the safe and make off with at least $350,000 worth of loose stones, jewelry waiting for repair and display pieces.
A Los Altos police spokesman says officers arrived 14 minutes later, but found only an empty jewelry store.