A federal judge says Apple should help the FBI break the encryption on a terrorists' cellphone. The Apple CEO says not so fast.

FOX's Rachel Sutherland reports:

Apple chief Tim Cook says the tech giant will fight the judge's order to help break encryption on an iPhone belonging to Syed Farook, one of the San Bernardino shooters.

These California residents are skeptical of police and phones:

(Man) "I won't even let my friends get into it, so why would I let the police?"

(Lady) "People think that it can be taken advantage of, that maybe the police are looking into more than what they say they're trying to find."

Cook says cooperating with the FBI would create a backdoor that could be used on future devices. Law enforcement officials say encryption can be a problem during investigations.

Rachel Sutherland, FOX News.

CLICK HERE to read the entire letter that Apple chief Tim Cook wrote in regards to the San Bernardino shooters