A father dressed as Santa Claus arrived to his family's Christmas party with two guns, executed his entire family and then killed himself -- and planned the entire thing, police said Tuesday.
Police believe the Christmas Day massacre in Grapevine, Texas, which left seven people dead still surrounded by Christmas presents and wrapping paper, was premeditated, Grapevine Police Sgt. Robert Eberling said.
Late Tuesday afternoon, Grapevine police officially released the name of the gunman and his victims.
Police confirm what family friends said Monday, that Azizolah "Bob" Yazdanpanah, 56, fired the fatal shots in the murder-suicide.
Grapevine police identified the victims as his wife, Fatemah "Nasrin" Rahmati, 55; their daughter, Nargis "Nona" Yazdanpanah, 19; and their son, Ali Yazdanpanah, 14. Nasrin's sister, Zohreh Rahmati, 58; her husband, Mohamad Hossein Zarei, 59; and their daughter, Sahra Fatemah Zarei, 22; were also killed, police confirmed.
Police received a 911 call from an apartment in the 2500 block of Hall Johnson Road on Christmas morning. When officers arrived, they found the door locked from the inside, and the worst crime in Grapevine history.
Police recovered two weapons on the scene -- a Smith and Wesson 915 model 9 mm pistol with a 15-round magazine, and a Glock 23 .40-caliber pistol with a 10-round clip, according to Eberling.
Both guns were used in the murder-suicide, but Eberling would not say how many shots were fired; only saying that there were still bullets in both guns.
Last year, a bank foreclosed on Bob Yazdanpanah's house, and he separated from his wife in the March.
Police had previously said a text message prior to the shooting indicated Bob Yazdanpanah was probably invited to the party, but police on Tuesday afternoon changed their story.
Police now say Bob Yazdanpanah apparently was not invited.
At 11:16 a.m., one of the victims sent a text message to a friend indicating who was at the gathering at the apartment. The text message mentioned the gunman's name and that he was dressed as Santa. Police said there was no indication of fear or concern in the text.
Eighteen minutes later, someone placed a call to 911 from a landline inside the apartment. Investigators could make out a muffled cry for help in the background, Eberling said.
All of the victims were found in the same room with no sign of a struggle, according to Eberling, but he said some of the victims had defensive wounds that indicate they tried to shield themselves from the bullets.
Police will wait for the Tarrant County Medical Examiner to release the identities of the victims, Eberling said.
The gunman had some prior dealings with at least two other police departments but not Grapevine Police, according to Eberling. He did not say what kind of dealings, or when or how many incidents there were.
Investigators are still piecing together information, but Eberling said they aren't sure of a motive and may never know what led to the worst crime in Grapevine history.
Friends paint picture of loving family in turmoil
Yazdanpanah married Fatemah "Nasrin" Rahmati in 1987, according to court records. They had a daughter, Nargis "Nona," 19, who graduated from Colleyville Heritage High School in May and a son, Ali, 15, a high school freshman. All four are believed to be among the dead.
Neighbors say the family seemed tight-knit, and Aziz Yazdanpanah seemed protective of his children.
"He was pretty outgoing," said neighbor Fred Ditmars. "If you saw him, he'd say 'hi' to you and everything."
"It seemed like their whole existence was about family, so it's utterly shocking to me," said another neighbor, Terri Baum, whose daughter attended school with his daughter.
A close friend of the Yazdanpanah family said Fatemah "Nasrin" Rahmati's sister Zohreh, her husband Hossein Zarei and their 22-year-old daughter Sahra were also killed.
Sahra (pictured left in blue) was a pre-med student at the University of Texas at Arlington, and according to family friends she was a part of the Tri Delta sorority at UTA.
"Bob loved his kids. And I can't even fathom that that's what happened," Baum said.
The mother, Fatemah "Nasrin" Rahmati, worked the past four years doing manicures at a salon on Southlake's town square. The manager said she often talked about her family, but never in a bad way.
Police cautioned the investigation is far from over.
NBC 5's Scott Gordon, Ray Villeda and Ben Russell contributed to this report
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