By Marice Richter
GRAPEVINE, Texas (Reuters) - Moments before police found seven bullet-riddled bodies in a suburban Dallas apartment on Christmas Day, someone from inside the home called 911 and asked for help, police said on Tuesday.
Police say it was likely the killer -- a man in a Santa suit who apparently gunned down his family before fatally shooting himself -- who called 911 before dying.
Law enforcement officials initially thought the call was a silent, open line, but they heard something else when they listened to it again on Tuesday, Grapevine Police Department Lieutenant Todd Dearing told Reuters.
"Right at the beginning of the call, you can hear someone breathing hard, and it sounds like they're saying 'Help,'" Dearing said.
"It's real soft, but when you put the earphones on, you can hear it a lot better. Then it's 30 seconds of heavy breathing, then the call disconnected."
The call from the Grapevine, Texas, apartment late Sunday morning prompted police to break down the door to find the bloodbath.
The victims ranged in age from 15 to 59, police said. Their bodies were strewn around the living room amid unwrapped presents and near a Christmas tree.
Two handguns -- one of which the shooter had owned for some 15 years -- were found at the scene, Dearing said.
Police have said the seven were members of two families connected by a pair of siblings, but have not released their identities, nor a motive for the killings.
But more details began to emerge on Tuesday as investigators pieced together clues about the worst massacre ever seen in this town of 46,000, known as the "Christmas Capital of Texas," about 20 miles from downtown Dallas.
Investigators were putting together a more precise timeline for the killings after interviewing friends and relatives of the victims, Dearing said.
That morning, one of the victims sent a text message to a friend or family member saying that he or she and two others had just arrived at the home, and that the man in the Santa suit was already there with three others, Dearing said.
There was no hint at distress in the message, Dearing said.
"It was an innocuous text," he said. "There wasn't a cry for help or anything like that. Nothing was amiss at that time."
But 18 minutes later, that changed with the 911 call.
Operators tried to call back, as is the standard procedure, but no one answered, Dearing said. By that time, police were on the other side of the apartment door, listening to the phone ring unanswered, he said.
Moments later, they broke down the door and discovered the scene.
"We have a small window there of when everything transpired," Dearing said.
Dearing said evidence seemed to indicate that the 911 caller was the shooter.
"We're not 100 percent on that, but it leads toward that," he said. "It sounds like a male and the way the scene is set up, he would be the more logical one."
The shooter had brought with him two handguns -- a Glock 40-caliber pistol with a 10-round magazine, and a Smith and Wesson 9mm with a 15-round magazine, Dearing said.
Dearing would not say how many casings had been found, but said neither gun's magazine was spent.
The shooter had owned both guns, one of which was purchased in 1996, for several years, Dearing said.
"He didn't go out and buy them the day before Christmas," Dearing said. "He's had them for a long time."
Lincoln Vineyards apartments, where the shootings happened, is a middle-income complex near Colleyville Heritage High School, one of the area's most highly regarded schools.
Grapevine is known for its wine-tasting salons. It was proclaimed by the state Senate as the "Christmas Capital of Texas" for its abundance of annual holiday-season events.
(Additional reporting by Karen Brooks in Austin; Editing by Jerry Norton)