The HTC Myst, widely believed to be the next Facebook smartphone, looks as if it's headed to the AT&T network, according to a recently unearthed Federal Communications Commission filing.

The FCC documents name the company as HTC and the device as PM33100, a model number that's previously been tagged as the HTC Myst and HTC Opera before that.

What's even more interesting is that the four LTE frequencies listed in the equipment test portion of the report are normally found in AT&T smartphones, concluded Engadget.

HTC, AT&T and Facebook haven't responded to TechRadar's inquiries into the FCC filing, but we'll let you know if and when they do.

HTC Myst specs

The HTC Myst specs are still shrouded in obscurity, as the FCC report doesn't reveal any more facts about the forthcoming handset.

However, previous rumors indicate this HTC phone may run Android 4.1.2 Jelly Bean and have a 4.3-inch screen with a 720p display at 320ppi pixel density.

Better yet, a 1.5GHz dual-core MSM8960 Snapdragon processor, 1GB RAM, and 16GB of internal storage should give HTC's next Facebook phone the bump that it needs over its predecessors.

HTC had previously released a pair of Facebook smartphones, the HTC ChaCha (HTC Status in the U.S.) and HTC Salsa, tied to the social network app, complete with a dedicated Facebook button.

How well the HTC Myst plays with Facebook and whether it contains a dedicated button for the app remains to be seen.

With the FCC filing squared away and the carrier most likely AT&T, the long-rumored HTC Myst Facebook should provide a proper official status update soon.