The mother of a man accused of killing his friend in Islip took the stand in court on Monday.

Prosecutors say Kyle Underhill, 18, had been bludgeoned, strangled and buried alive under pieces of plywood in an Islip creek in November 2011. His friend and high school classmate Thomas Liming, now 23 years old, is facing second-degree murder charges in Underhill's death.

Liming's mother Kim took the stand Monday in a fourth-floor courtroom. She testified that her son was shaking, crying and in shock the night of the killing, and she could tell that he was in a fight. She says she called 911 saying that her son had been attacked, telling the operator that Underhill had done it.

Later, during cross-examination, the prosecutor asked Kim Liming, "You know your son killed Kyle Underhill?" She answered, "My son defended himself." The prosecutor pressed, "Is that a yes, ma'am?" Liming replied, "Yes."

Suffolk County District Attorney Thomas Spota and Underhill's mother were also present in court.