A jury of eight men and four women deliberated for nearly seven hours before reaching their verdict.

Deanna Laney, 39, broke down in tears and shook when state judge Cynthia Kent read the jury's decision in the hushed courtroom in the eastern Texas city of Tyler.

She could have faced life in prison if convicted, but instead will go to a state mental institution until the judge decides she is well enough to be released.

Defense attorney F.R. "Buck" Files told reporters he felt "relief" at the verdict, but said Laney's suffering over the killings would never end.

"She is in a living hell," he said.

Laney was a deeply religious woman who home-schooled her children before mental illness drove her on May 10, 2003 to kill Joshua, 8, and Luke, 6 and injure Aaron, now 2, Files said during the trial.

Prosecutors said she led the two older boys separately out to the garden of their house in the town of New Chapel Hill, told them to lay their heads on a stone, then used a rock to bash in their skulls.

She also struck 14-month-old Aaron with a rock while he lay in his crib. He survived, but is blind and brain damaged.

Four mental health experts, including two hired by the prosecution, testified that Laney was clearly insane, but Smith County District Attorney Matt Bingham disagreed.

He argued that Laney was not insane because she called police to tell them she had killed her sons, which showed she knew she had done something wrong.

Under Texas law, a person is not legally insane if they know while committing a crime that it is wrong.

In chilling videotaped interviews afterward, Laney explained without much remorse that God told her to kill the boys with stones.

She said she and Andrea Yates, a Houston mother who drowned her five children in the family bathtub on June 20, 2001, had been called to be witnesses for God.

"I thought we were going to be two witnesses to the end of time," she said.

Yates, who had a long history of mental illness, pleaded not guilty by reason of insanity, but was found guilty and sentenced to life in prison.

Laney had never been treated for mental problems and witnesses, including husband Keith Laney, said they never saw any signs she was disturbed. He said they were heavily involved in the local Pentecostal church and were living an idyllic life until the killings.