Yes. Apparently they identify which room has the smoke in it. An automatic weapon emits a ton of smoke. Rather handy.
I've heard some reports of muzzle flash but I cannot see it in the three video clips I have seen. It ought to be easy to spot, I think.
On the other hand, the estimated response timeline is shocking.
About 10pm: Paddock smashes out two windows on the 32nd floor with a hammer-like implement and opens fire with his arsenal of at least 19 weapons - including fully automatic weapons.
10.08pm: First phone call to police that shots had been fired at the festival outside the Mandalay Bay Hotel and Casino on the Las Vegas Strip.
10.38pm: Police in Las Vegas say that they are 'investigating reports of an active shooter' near to the Mandalay Bay.
11.08pm: Las Vegas police confirm they have shut down a portion of The Strip
11.20pm: SWAT teams storm the 32nd floor room that Stephen Paddock was firing from. They gained entry using flashbangs designed to stun the shooter. Officers entered the room and found he had taken his own life. Seventy-two minutes elapsed from the first 911 call to Paddock being found dead.
11.20pm: Hundreds of people began being transported to hospitals in Las Vegas
11.32pm: McCarran International Airport announced it was diverting flights destined for the city.
11.34pm: Interstate 15 in and out of Las Vegas was shut down for a time.
11.56pm: Hospitals in Las Vegas said that at least two people were dead and 24 were injured of which 12 were critical.
12.01am: Almost two hours after the first emergency call police confirmed that one suspect was 'down'.