PORT ST. JOHN, Fla. (AP) — In the middle of the night, Tonya Thomas’ neighbors awoke to the sound of a gunshot and moments later heard a knock on their door.

Three of Thomas’ four children were outside, including one who appeared to have been shot. Before the neighbors could offer help, Thomas came out of her house and called the children back home.

They complied. The neighbors dialed 911 after hearing more gunshots.

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Brevard County Sheriff’s deputies found Thomas, 33, dead of an apparent self-inflicted wound and three of her children — Jaxs Johnson, 15; Jazzlyn Johnson, 13; and Joel Johnson, 12 — were fatally shot inside the house. A fourth child, Pebbles Johnson, 17, was found shot to death in the front yard of a neighbor’s house.

Investigators said they didn’t know a motive for the shooting and weren’t sure why the children followed their mother’s orders to return to the house.

“From what the neighbors said, she was very calm. She walked out and called them back. They turned around and walked back to the house,” said sheriff’s spokesman Lt. Tod Goodyear.

Another neighbor told deputies Thomas sent a text message in the middle of the night saying she wanted to be cremated with her children.

“He didn’t see the text until he woke up this morning,” Goodyear said.

The shooting happened in Port St. John, about 15 miles west of Cape Canaveral in an area known as the “Space Coast” because it is the home of NASA’s Kennedy Space Center, the location of numerous shuttle launches.

Authorities went to Thomas’ house on three successive days last month, according to dispatch records released Tuesday.

In the first visit, on Easter Sunday, Thomas reported that her son had thrown a bicycle through a window at the house. The next day, she called to report that her son had kicked and punched her when she tried to wake him up for school.

The following day, child welfare investigators visited the house to look into allegations of inadequate supervision of the children.

The Department of Children and Families was following up on a report on a Johnson child who had been released from a detention facility and hadn’t been picked up by a caretaker, DCF spokeswoman Carrie Hoeppner said in an email.

Records showed Thomas was arrested in 2002 on a misdemeanor battery charge for striking Joe Johnson, the father of her children. The charge was later dropped. Two years earlier, she filed a domestic violence complaint against Joe Johnson, but that was dismissed after a hearing.

Jamie Hudson, whose mother lives two doors down from the family, said the boys in the family were known to shoot BBs at a home across the street and had threatened to set it on fire.

“It has been an ongoing problem on our street with them,” Hudson said.

Goodyear said Jaxs Johnson had recently been arrested on a domestic violence charge. He said he didn’t know if the boy had been accused of hitting his mother or causing damage at the house.

Austin Lewis, a 16-year-old classmate of Pebbles Johnson, said the family “had problems like everybody else but nothing that drastic.”

He described Pebbles Johnson as “very loving and caring.”

“Always with a smile,” Lewis said. “Didn’t let anything affect her. She was always in a good mood.”

A pastor at the church the family attended described it as “normal stuff.”

“I think he was punching some walls or something,” said Jarvis Wash, pastor of the Real Church in Rockledge, Fla.

Wash said the family attended services last Sunday but had been absent for a few weeks before that.

“I don’t know what could have happened in the past couple of days,” Wash said. “It’s a tragedy to the church and the community.”

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Copyright 2012 The Associated Press.