SAN JOSE (KPIX) — In the heart of Silicon Valley’s biggest city, during standoff that claimed the life of a fellow officer, KPIX 5 has learned the mobile computers used by San Jose Police officers went completely offline for hours, forcing officers to use archaic radios and even placing individual cellphone calls to coordinate the emergency response.

Police computers were working, but unable to connect to send and receive data, according to officers speaking to KPIX 5’s Len Ramirez.

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The problem existed all over the city, according to sources, and impaired coordination with neighboring agencies and arriving officers.

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The standoff ended with the murder of Officer Michael Johnson, a 14-year veteran of the San Jose Police Department at the hands of Scott Dunham, shooting from the cover of his enclosed second-story balcony. Another officer shot the 57-year-old Dunham dead shortly after on Tuesday night.

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