FBI Director James Comey said the secret method the organization had applied to hack into the iPhone used by the man and woman who killed 14 people in San Bernardino in December does not work on other models.

"We have a tool that works on a narrow slice of phones," Comey said on Wednesday.

He said that the FBI purchased the tool from an outside party and that it would only be of use with the iPhone 5c running version 9 of Apple's mobile operating system.

Apple vs. FBI

The FBI engaged in a showdown with Apple last month after the tech giant refused to unlock the phone, arguing that it was an example of government overreach. The Justice Department, of which the FBI is a part, obtained a court order directing Apple to disable the password protection on the phone.

Apple won popular support from many for standing up to the government. However, the showdown came to an abrupt end when the FBI announced it had found a way to hack into the phone.

Meanwhile, the Justice Department has also asked a court to order Apple to unlock another phone in connection with a drug investigation. A court order still has yet to materialize.

blc/jm (AP, Reuters)