A Michigan Uber driver accused of murdering six strangers between fares pleaded guilty on Monday, shortly before jurors were set to be interviewed for his trial, according to the Associated Press

Jason Dalton, 48, ignored his attorney's advice - triggering a mandatory sentence of life in prison with no chance for parole, in a surprise move that comes more than three years after the shootings which occurred over the course of a few hours in and around Kalamazoo.

"I've wanted to do this for quite a while," Dalton told a judge. 

Following his arrest, Dalton told police that a "devil figure" on Uber's app had been controlling him on the day of the shootings. That said, he was found competent to stand trial last week and dropped an insanity defense. 

The 48-year-old Dalton answered "yes" to a series of questions on Monday, admitting that he shot eight people at three locations. Four women were killed in the parking lot of a Cracker Barrel restaurant, while a man and his 17-year-old son were fatally shot while looking at cars in a dealer's lot.

A girl who was 14 at the time was shot in the head during the restaurant shooting but survived. Another woman was injured in a residential area. -Associated Press

Eusebio Solis, Dalton's attorney, says he advised his client not to plead guilty, but that Dalton wanted to spare families more grief during a trial. 

"I've been practicing law for 30 years and have never pleaded to life in prison without parole," said Solis outside the courthouse. 

Dalton, a father of two children, had no previous criminal record and worked as an insurance adjuster. 

According to gun shop owner Jon Southwick, Dalton bought a jacket with a special pocket designed to hold a gun just hours before the rampage. He said the Uber driver was "laughing and joking" and gave a "one-armed hug" before the manager right before making the purchase.