Police have arrested the husband for murder.
The man turned himself into police Wednesday.
Investigators say he came into the department's lobby, and told a clerk he had killed his wife.
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When police went to the home, they found the wife and the suspect's 11-year-old daughter dead.
"This is just a horrific tragedy," said Sunnyvale Police Captain Craig Anderson.
"Our heart are broken for the family, for the victims and all of their friends," Capt. Anderson said.
Neighbors visited the home this morning and left flowers.
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