(Varner-AP) -- Christina Marie Riggs was executed by lethal injection at 9:28 p-m- at the the Arkansas state death chamber at Varner. She was condemned after being convicted of two counts of capital murder for killing her children, five-year-old Justin and two-year-old Shelby Alexis.
Riggs smothered both children but first injected Justin with potassium chloride, one of the same drugs administered to her last night.
The execution began at 9:18 p.m. Riggs made a final statement in which she expressed sorrow for the murders. She said -- quote -- "There is no way no words can express how sorry I am for taking the lives of my babies...."
Her final words were -- "Now I can be with my babies, as I always intended."
As the execution began, Riggs' bottom lip quivered. She closed her eyes and lay almost perfectly still as she died.
Riggs was the first woman executed in Arkansas in 155 years, and the fifth nationwide since the U-S- Supreme Court reauthorized capital punishment in 1976.
The former nurse from Sherwood asked her jury to sentence her to death for the November 5, 1997, slayings.
After her conviction, she pursued appeals at her family's request but withdrew them this year after a judge ruled that she could. The state Supreme Court later upheld her request, clearing the way for her execution.
During her trial, prosecutors said Riggs' children had become an inconvenience to her. They said she left the children by themselves while she competed in karaoke contests and that she plotted their deaths for two or three weeks.
Riggs' lawyer, John Wesley Hall of Little Rock, called the execution a -- quote -- "state-assisted suicide."
Hall said Riggs' conviction and death sentence was unconstitutional because she was depressed and mentally unstable. He also said his client believed she would go to heaven because the state killed her.