Texas has only been an open-carry state since January

People at an open carry rally in Texas this January. — (Image credit: Erich Schlegel/Getty Images)

Sniper fire targeting law enforcement erupted at a peaceful protest in Dallas late Thursday night, with at least 11 officers shot and four killed. Protesters had been marching after the fatal officer-involved killings of Alton Sterling in Baton Rouge, Louisiana, and Philando Castile in Falcon Heights, Minnesota.

The Dallas Police Department initially circulated as a person of interest a photo of a man wearing a camouflage shirt and carrying a rifle, who later turned himself in to police; the man's brother told CBS's Dallas affiliate that his brother had given his rifle over to a police officer earlier and later tweeted that he is not a suspect in the shooting.

The confusion possibly arose because Texas is an open-carry state, after a bill signed by Gov. Greg Abbott (R) last year took effect in January. With the correct license, it is legal in the Lone Star State to openly carry a handgun, provided you are at least 21 years old, have no prior criminal record, and have completed required training and education (before the new law, a person could open carry a long-gun, like a sniper rifle). Certain public spaces, like schools and courtrooms, are still gun-free — but at an event like Thursday's protest in Dallas, which consisted of an outdoor march down an open street, open-carry enables individuals to carry weapons freely. Media has speculated that because anyone at the protest could have conceivably been carrying a weapon per the open-carry law, identifying the actual suspects may have been more difficult. Read more about Texas' open-carry law here.