AT&T

AT&T has offered a $250,000 reward for information leading to the arrest and conviction of the people responsible for vandalizing its network in the heart of Silicon Valley.

In what appears to be coordinated acts of vandalism, fiber-optic cables near San Jose, Calif., were cut in two locations early Tuesday morning before shots were fired at electric transformers at a nearby PG&E substation. Damage to the underground cables, which are accessible by manhole covers, prevented residents of the city of Gilroy to the south from using landlines to make 911 calls for emergency service.

The objective appears to have been "shutting down the system," Santa Clara County Sheriff Laurie Smith told reporters at the substation this afternoon, according to a Gilroy Patch account of the news conference.

"All of this occurred within a half mile radius so because of the time frame and because of the geographical distance that these things happened, we believe that it's related," Smith said.

All 911 service was restored this evening, but phone service is not expected to get back to normal until Wednesday morning, AT&T spokesman George Ross said.

A similar act of vandalism occurred four years ago this month in south San Jose, causing a widespread telecommunications outage in southern Santa Clara and Santa Cruz counties. It wasn't immediately clear if any suspects had been identified in that case.

The sheriff's department is also investigating the PG&E shooting, which left at least five transformers damaged, spilling hazardous chemicals used to cool the electrical equipment. No service outages occurred as a result of the damage, but state power grid authorities issued a bulletin asking local residents and businesses to conserve electricity until midnight.