Authorities on Monday arrested a Baton Rouge man accused of fatally shooting an 18-year-old girl and critically injuring her stepfather in a Friday afternoon shooting at a North 30th Street home.

The suspected shooter, 26-year-old Quintin Thomas, was arrested Monday in Lafayette and brought to the East Baton Rouge Parish Prison on Tuesday, said Cpl. L’Jean McKneely, a Baton Rouge police spokesman.

Thomas was booked Tuesday into Parish Prison on counts of first-degree murder, attempted first-degree murder and illegal use of a weapon in the shooting that left 18-year-old Idalis Smith dead and the other man injured, McKneely said.

Police in Baton Rouge also arrested Victoria Guillory, a 23-year-old woman identified by police as Thomas’ girlfriend, on a count of accessory after the fact to first-degree murder, McKneely said. Guillory was booked Tuesday into Parish Prison on the accessory count.

Police have yet to establish a motive for the killing, and the shooting remains under investigation.

Smith’s family members have identified the man injured in the shooting as 34-year-old Greg Dosson, Smith’s stepfather. Police have said the man was taken to a hospital in critical condition and underwent surgery after the shooting, which occurred at about 1:10 p.m. at the house on 1305 N. 30th St.

McKneely said the injured man remained hospitalized on Tuesday.

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