Here's the photo that has been broadcast by a local NBC affiliate, which says it is in the process of confirming the authenticity of the surveillance image:
This image appears to depict a male, likely in his twenties, carrying an AK-47 style firearm with a fixed wooden stock. The fact that he's wearing hearing protection and possibly shooting glasses may indicate some familiarity with rifle fire as well as a bizarre, twisted logic. Apparently, he wants to kill innocent people but doesn't want to suffer hearing damage during the rampage. This indicates the possibility of extreme mental illness.
The following photo was tweeted by a reporter on the scene, along with the claimed name of the shooter being "Patrick Crusius" from Dallas, Texas:
UPDATE: The El Paso police, which originally told the media the event was "gang-related terrorism" is now "walking back" that claims, according to media reports. You are watching the narrative being altered in real-time as the fake news media is trying to twist this event into the narrative they want. Namely, they want the shooter to be an immigrant-hating Trump supporter who watches InfoWars and has a membership with the NRA. Even if none of that is true, they are going to keep twisting the facts to get the narrative they want.
The fake news media fabricates everything to twist reality into their false narratives.