There have been 11 similar cases of residential burglaries in Palo Alto since October, officers announced on Sunday.
Investigators from the Palo Alto Police Department identified a trend of burglars stealing jewelry and safes from empty homes between 7 and 9 p.m.
The homes targeted so far are spread across the city's neighborhoods, and not all had their alarm systems triggered. But in all cases, the homes were unoccupied and ransacked of jewelry and safes.
The thieves usually entered by smashing glass doors in rear yards, according to a statement from Palo Alto police. In one robbery, a locked gun safe with nine firearms—all of which were legally owned and registered—was taken.
Investigators believe the crimes have been committed by the same group of two to four suspects, identified as men in their 20s, based on available surveillance footage.
No arrests have been made, and the suspects still remain at large, said police. Local investigators are also reaching out to other law enforcement departments in the area to see if there have been similar incidents in other jurisdictions.
In response to the uptick in burglaries, police are increasing patrols in neighborhoods. Residents are urged to report suspicious activity at (650) 329-2413.