Minneapolis police have made an arrest in the Tuesday slaying of Jessica St. Marie in south Minneapolis. A 50-year-old man was booked into Hennepin County jail Saturday morning on probable cause murder, police said.

The suspect is accused of fatally shooting St. Marie, 28, during an argument at a bus shelter at the corner of East Lake Street and Park Avenue S.

Witnesses said St. Marie was waiting for a bus just before 7 p.m. when she was shot in the head by a gunman, who then fled down a nearby alley. The was taken to Hennepin County Medical Center, where she died.

In a span of just three days, five people have been shot and killed in St. Paul and Minneapolis. As of Saturday morning, this is the only arrest police have made in any of the cases as they scramble to figure out who fired the fatal shots and why.

The Star Tribune generally does not name a suspect until he or she has been charged.

Check back at startribune.com for continuing developments.

Libor Jany • 612-673-4064