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The friends entered the home through an unlocked glass door after not hearing from the Rabbis for a few days.

One friend who did not want to be identified told KGO the bodies were found with a message written in ink that said, "Sorry, my first kill was clumsy."

The couple were devout members of a nearby Islamic center. Members of the center are grappling with the loss.

The Rabbis, who immigrated from Bangladesh decades ago, were described as "simple, gentle souls" by one member of the Islamic center they attended.

KTVU reported that police found the bodies at 2 p.m. Sunday.

The circumstances of the couple's death is not known.

Golam Rabbi worked as an engineer. Shamima Rabbi worked as an accountant.

The couple leaves behind two sons, 17 and 21.

Police do not have a suspect yet.