A 21-year-old man with mental health issues who allegedly shot three people, stole a car and struck and killed a Memphis police officer Saturday was charged with first-degree murder on Sunday.

Authorities said officers previously made an emergency commitment of Justin Welch in December 2013, two and a half years before the crime spree that ended in the death of Officer Verdell Smith.

Welch is also charged with vehicular homicide, evading arrest, theft and reckless driving.

Police have not yet established a motive.

Smith, 46, was an 18-year veteran of the police force. He’s survived by a father, fiancé, son and two daughters.

"This highlights the dangers officers face every day," Memphis Police Department Director Mike Rallings said.

Police said two people were in critical condition after Welch shot them near a Westy’s restaurant at about 10:00 p.m. They said Welch then ran into a Bass Pro Pyramid and shot a male employee. The condition of the employee wasn’t immediately known.

Martin Norris and Jake Schorr IV, two Westy’s employees, told the Memphis Commercial Appeal that a man was talking loudly to himself, walked up to two customers who were sitting at a picnic table in front of the restaurant and shot them.

Police said Welch fled in a vehicle and struck Smith.

Memphis Mayor Jim Strickland urged the city in a statement to pray for Smith and his family.

 "I am angry this morning -- angry at the senseless loss of a dedicated public servant, and angry at the absolutely unacceptable level of violence in our city," Strickland said. "We must not accept this as our norm. I most certainly will not, and I will continue to act to make our city safer."

The Associated Press contributed to this report.

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