UPDATED at 10 a.m. Wednesday with further details about the incident.

UNIVERSITY CITY • A Florissant man was charged with grabbing a pistol from a woman Monday as she was trying to prevent him from attacking her friend in University City, then beating her and her friend with the gun and shooting one of the women.

Police said Mario Pearson, 31, of the 2600 block of Northridge Place, had hired the two women for sex. One pulled a gun out when Pearson became aggressive, police said.

Pearson was charged Tuesday with first-degree assault and armed criminal action. He was being held on a $150,000 bail.

Police said officers were summoned about 3:50 p.m. Monday to a call for a robbery at a vacant home in the 1200 block of Meyer Street. Once there, police found the injured woman, who had been shot in the chest.

Police said Pearson had hired the woman, 23, and her friend, 21, for sex. When Pearson became aggressive with the 21-year-old woman, the 23-year-old woman pulled out a handgun in an attempt to defend her friend, police said.

Pearson then took the gun and beat the women with it. He shot the woman who had originally pulled the gun, police say. She was struck twice in the chest. Police said the woman who was shot had a permit to carry a concealed weapon.

Police said the shooting victim was in critical condition. Pearson's criminal history includes a 2014 conviction of unlawful use of drug paraphernalia, a misdemeanor.

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