Fort Lauderdale (United States) (AFP) - A US jury on Thursday rejected the death penalty for Nikolas Cruz, who shot and killed 17 people at his former Florida high school, opting instead for life imprisonment without the chance of parole.

The jury deliberated for a full day Wednesday and briefly Thursday before deciding that the 24-year-old Cruz should receive life in prison for the February 2018 murders of 14 students and three staff members at Marjory Stoneman Douglas High School in Parkland, Florida.

A death penalty recommendation needed to be unanimous and at least one or more of the 12 jurors found it was not justified because of mitigating circumstances.

As the verdict was read, Cruz, wearing a striped sweater and large glasses, stared down expressionless at the defense table while several relatives of the victims in the public gallery shook their heads in disbelief.

Cruz pleaded guilty to the Valentine’s Day murders last year and prosecutors had argued during a three-month penalty trial that the appropriate sentence was death.

Melisa McNeill, a lawyer for Cruz, had urged the jurors to show mercy to a young man she described as a “brain-damaged, mentally ill, broken” person.