It took two days, but the companies' entry solidifies a small but powerful band of tech giants supporting Apple in its quest to buck government demands that it says would irreparably damage security and erode consumer trust.
Among the first to come to Apple's defense was its chief rival. Chief Executive Officer Sundar Pichai of Alphabet Inc's Google tweeted in support of Apple on Wednesday.

But other companies are staying mum. Yahoo Inc and Microsoft Corp have yet to weigh in on the case.

In characteristic fashion, Twitter CEO Jack Dorsey used the service itself to lend support to Apple CEO Tim Cook, tweeting "We stand with @tim_cook and Apple (and thank him for his

In a statement, Facebook said, "We will continue to fight aggressively against requirements for companies to weaken the security of their systems."

The case has intensified the rift between tech companies and law enforcement over the limits of encryption. And law enforcement groups have been vocal about their support for the Justice Department.

Also read: Sundar Pichai backs 'Apple' over unlocking terrorist's iPhone