BOULDER, Colo. -- Dozens of people in Boulder outside for weekend activities called 911 after seeing two planes collide Saturday afternoon.

7News obtained nearly three dozen 911 calls placed to Boulder police in the moments following the plane crash.

Bob Matthews, 58, and his brother Mark Matthews, 56, were both killed, when the Cirrus SR20 they were in collided with a Piper Pawnee towing a glider. The pilot of the Piper Pawnee, Alex Gilmer, 25, also was killed in the crash. Three people inside the glider survived. Pilot Reuben Bakker landed the glider safely. Brandi Hepburn and her 11-year-old son, Javen McDonald, were passengers in the glider.

Boulder Police Department 911 Calls

911: "911, where's your emergency?"

Caller: "Yeah, we just saw a plane crash or something, it exploded in the air. It's got flames coming down, a parachute on fire."

That was the first of dozens of 911 calls received by the Boulder Police Department.

911: "911, what's the emergency?"

Caller: "Hi, I think I just saw two planes collide."

"There's one aircraft that's still circling," said another caller in reference to the glider.

Caller: "Something just fell out of the sky. There is a lot of smoke and it might be an airplane."

Call after call referenced either an airplane explosion or two airplanes which collided. 911 dispatchers struggled to find an exact location of the crash.

Caller: "I witnessed I think it might have been a plane blowing up?"

911: "OK, do you have any idea where it hit?"

Caller A: "Something just blew up in the air, some plane."

Caller B: "It looks like it's over Wonderland Lake, I think I just saw a plane crash."

Caller C: "I actually don't have an emergency, but I just saw a flaming parachute land in North Boulder."

911: "Do you know where? Do you know where!?"

911 even received a phone call from a Federal Aviation Administration employee working in a Denver monitoring station.

FAA Caller: "We got a call from [Rocky Mountain] Metro Airport Control Tower about a possible mid-air collision between two aircrafts east of the Boulder Reservoir. Have you had any calls about that?" 911: "Oh yeah. Possible mid-air collision."

One caller, near the crash site, told dispatchers to send crews to a field near the American Legion Post at 4760 28th St.

Caller: "There is a plane that just caught on fire in mid-air and came crashing down. We're going to need an ambulance and a fire truck."

Boulder County Sheriff's Office/Fire Dispatch Traffic

Boulder County Sheriff's Deputy [1:28 p.m.]: "Yeah, I'm not exactly sure what I just saw, I'm about 39th and Nelson -- break."

Dispatch: "We're getting calls of a plane crash on Highway 36, just north of Boulder, is that what you saw?"

Deputy: "That's what I see."

Dispatchers reported to responding units numerous phone calls from the public reporting a plane collision.

Dispatch: "Believe two separate crashes, two separate fires at 13:30 [1:30 p.m.]. We're getting reports of a possible parachute deployed and also debris falling…we've got a minimum of two fires and we're still getting flames."

Deputy #2: "I'm coming up on it right now. I've got one plume of smoke at the coffee plant and I've got another one in the field to the east there, about a mile out, and I've got fire on the ground."

Deputy #3: "Sir, I'm getting reports it was a plane here, and I'm just getting bits of debris across here. I've got nothing bigger than just pieces of metal right now…witnesses seen this going down, if we can get units to the largest plume of smoke, that appears to be where the parachutist went down. We've not found any victims in the field yet up by the smaller two fires."

It was learned after the crash, the parachute was an emergency mechanism attached to the Cirrus SR20.