According to authorities, the suspect of the Colorado Springs shooting allegedly opened fire and killed six people at a birthday party reportedly because he was disappointed at not being invited to the event. The police chief said that Teodoro Macias, 28, had been dating Sandra Ibarra, one of the six victims, for around one year.

Gunman Upset He Was Not Invited to the Birthday Party

His girlfriend's family threw the weekend gathering, the police added on Tuesday. They touted the core of the shooting as an act of domestic violence.

According to Colorado Springs police Lt. Joe Frabbiele, Macias had a history of exhibiting controlling and jealous behavior. Police stated there were no reported incidents of domestic violence in the course of the relationship. The shooter did not have a criminal history, reported ABC 7.

Although no protective orders were set forth, according to Police Chief Vince Niski, the shooter had exhibited power and control issues in the relationship, reported ABC News.

Frabbiele remarked that Macias walked into the mobile home in the 2800 block of Preakness Way and fired shots deliberately and quickly. He then killed himself right after, reported The Denver Post.

Niski added that no family should experience that type of loss. The party was thrown for three relatives. Two of them were killed.

The attack came less than two months following a mass shooting that recorded 11 fatalities at a grocery store in the north-central Boulder city in Colorado. Police officials remarked the Colorado Springs gunman had a "conflict" with the targeted family at a separate event around a week earlier, reported BBC.

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Gov. Jared Polis (D-Colorado) has commanded flags to be lowered to half-staff to commemorate the mass shooting victims until Sunday, May 16. Colorado Springs Police Department (CSPD) released further details on their probing and what led to the shooting at a news conference.

Other victims of the shooting on Sunday were Ibarra's extended family members. They were identified as Mayra Ibarra de Perez, 33; Melvin Perez, 30; Jose Gutierrez, 21; Joana Cruz, 52; and Jose Ibarra, 26.

Investigators do not know yet how the shooter acquired the weapon. Frabbiele described it as a Smith & Wesson handgun. He said another individual initially purchased it in 2014 at a local gun store. However, it was not reported stolen. The gunman had two 15-round magazines. One of them was empty. Police also obtained 17 spent shells at the scene.

Three children aged 2, 5, and 11 were unharmed. However, police said there is proof that they witnessed what transpired. A seventh adult was unharmed.

According to Frabbiele, all children were orphaned by the shooting. They were transferred to the custody of relatives. Police officials said the families of the victims had requested privacy.

Two families were celebrating their family members' birthdays. Ten people were inside the home when the suspect arrived. Police officials received the first of three 911 calls from within the house.

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