Violent past of alleged mass shooting gunman Ronald Lee Haskell

HARRIS COUNTY, Texas – Many disturbing details are surfacing about the violent past of a man accused of killing six members of his ex-wife's family -- including four children -- and critically injuring a teen girl.

The injured teen was able to tip deputies off to his next intended target, bringing Ronald Lee Haskell's shooting spree to an end. After an hours-long standoff with SWAT negotiators, the 33-year-old was taken into custody.

Haskell is the ex-husband of Melanie Kay Haskell. Melanie's sister, Katie Stay, lived with her husband, Stephen, and five children in Spring. On Wednesday, investigators say the Stay's 15-year-old daughter, Cassidy, answered a knock at the door that changed all of their lives forever.

According to court documents, Cassidy said her "ex-uncle" was wearing a FedEx shirt when he came to their home asking for her parents. When she told him they weren't there, he left, but returned a short time later. The second time, investigators wrote that he forced his way inside.

The documents state Haskell tied Cassidy up and waited for the rest of her family to come home. When they did, they were all bound and forced face-down on the floor. The court documents read that Haskell asked his in-laws where his wife was, and when no one could tell him, he shot them all execution-style. Court documents state he shot each one in the head.

The bullet meant to kill Cassidy only fractured her skull, and investigators say the teen played dead until her uncle left. Afterward, she called 911 for help.

Investigators say Cassidy put up her hand when she was shot, deflecting the bullet just enough to change its trajectory and save her life. We're told she lost a finger in the shooting.

Cassidy gave officers valuable information, saying she believed Haskell was going to kill her grandparents. Authorities managed to cut him off and after a police chase and a standoff for several hours barricaded by SWAT vehicles, he lowered the gun he held to his head and gave up.

Ronald Haskell was jailed with no bond and charged with capital murder.

Records show it wasn't his first run-in with the law, nor was it his first criminal act involving his wife or children. Records show the family had domestic issues in Utah.

According to the Cache County Sheriff's Office, Haskell has had several involvements with the Logan City Police Department and was incarcerated in the Cache County Jail in 2008.

NBC News Investigative Unit uncovered a police report from June 2008. Melanie Haskell called police and told investigators her husband had dragged her out of the bedroom by the hair and hit her in the side of the head. Ronald Haskell, however, said he had simply pushed her. Both told officers that he was stressed at work and they were not getting along. The report noted that there were two children, believed to be ages 3 and 5, home with them at the time. Ronald Haskell later pleaded guilty to a charge of simple assault. The crime was considered a misdemeanor.

In September 2009, NBC News Investigative Unit learned Ronald Haskell flagged down a police officer in Utah and told them that his wife had gone missing. He said Melanie left a note saying she was going away and would miss him and their children, and that she was holding them back. Ronald said he thought Melanie would kill herself. Police put out a bulletin, but Ronald later said he had found his wife and was taking her to the hospital.

Then on July 8, 2013, Melanie Haskell filed a protective order against her husband in Utah. He was served the following day, exactly one year before he allegedly killed her sister's family.

Melanie Haskell filed for divorce in August 2013. In October of that year, a protective order she filed against Ronald was dismissed as they both agreed to a mutual restraining order in the divorce action. The parties also agreed to custody arrangements involving the children. The judge said that Ronald Haskell's visits were to be supervised by a psychologist.

"The parties agree that Ms. Haskell will have primary physical custody with the parties having joint legal custody. Mr. Haskell will have a breaking parent time period working into standard visitation. Mr. Haskell's parent time will be supervised until such time that his physical therapist can report that the  respondent is no longer a threat to the children," the judge wrote.

Ronald Haskell's family members were also concerned about him.

During the divorce proceedings, Ronald Haskell's brother called from California and asked police to conduct a welfare check.  He said he was worried Ronald would hurt himself because he was upset about the divorce.  The brother then called back later and withdrew his concerns, telling them he had talked to him.

And just last week, on July 2, 2014, Ronald Haskell's mother called police in San Marcos, California. She told officers that Ronald became angry after she made contact with his ex-wife. Court documents show Haskell forced his mother into the garage where he taped her wrists together with duct tape and taped her arm to a chair. Karla Haskell told investigators he yelled at her and tried to choke her, causing her to pass out.

Karla Haskell told police he threatened to kill her and her family. Court documents show she was tied up for four hours. She described injuries around her neck and shoulder. A temporary restraining order was granted and a court hearing was scheduled for July 25.

But investigators say Ronald Haskell went on a shooting rampage Wednesday killing Katie, Stephen, Rebecca, Emily, Bryan and Zachary Stay. The children were all between the ages of 4 and 13.

Their family members say because Cassidy survived, the lives of other family members were possibly spared.