"As the FBI and local authorities launched an investigation, their focus was expected to probe militant black rights groups set up in Dallas. Anti-police groups include the New Black Panther Party and Huey P. Newton Gun Club, named after the founder of the 1960s activist Black Panther Party."
There's absolutely nothing here to link the shootings to this group or Islam except the musings of some unknown writer at The Australian (the source of that quote).
They all worked together in Ferguson, and other places.