MONROE — A 19-year-old will serve at least 27 years and nine months in prison after pleading guilty to murder.

Ivan Martinez, formerly of 3452 Walkup Ave. in Monroe, pleaded guilty to the Dec. 1, 2007, killing of Maria Elvira Celedon and her boyfriend Carlos Armando Arteaga DelAngel, who were killed in their home at 5703 Secrest Short Cut Road. Martinez could be incarcerated up to 31 years if he serves the full term.

Martinez is the third person to plead guilty to the double homicide after Ubaldo Trejo Martinez, 19, formerly of 886 Sunset Drive in Monroe, pleaded to two counts of second-degree murder and one count of kidnapping three weeks ago. District Attorney John Snyder would not get into specifics about the plea deals because there are still two others who have been charged in the killing.

Ivan Martinez’s attorney, Wayne Covington, told Superior Court Judge David Lee that Martinez thought the group was going to the house on Serest Short Cut Road to commit a robbery, not to kill anyone. Covington said his client did not pull the trigger of any weapon that killed DelAngel or Celedon.

Entering the plea deal allows Martinez to possibly live many more years after imprisonment ends.

“It’s tough to deal with numbers of that nature when you are dealing with a teenager,” Covington said.

Autopsies showed that DelAngel was shot six times and Celedon was shot nine times. Police found $47,000 in cash and $80,000 in cocaine at the house.

Martinez’s mother sat in the front row of the public section while he entered his guilty plea. During a recess before court came to order she reached across the barrier in the courtroom and sobbed while clinging to her son. After police took Martinez away in handcuffs, his mother left the courtroom and wept in the hallway. Martinez was a senior at Forest Hills High School when he was arrested two years ago.

According to court files, when police arrived at the scene they found DelAngel’s sister, Maricela Arteaga DelAngel, who was with the 6-year-old son and 4-year-old daughter of the couple who were killed. Maricela DelAngel told police she hid with the children in the bedroom until police came into the house.

Union County Sheriff’s Office Detective Brian Helms said the men that entered the house each had “assault-type rifles.”