Updated 11 a.m., Friday Jan. 12 -- Two people have died and one person was injured after two separate shootings in Roxbury and Dorchester on Thursday, police said.

The shootings took place within 20 minutes of each other. The Roxbury victim and and one of the Dorchester victims, both men in their 20s, died from their injuries Thursday afternoon.

Police patrolling on foot near 31 Whittier St. in Roxbury heard the sound of gunfire at 1:46 p.m. They found a victim suffering from gunshot wounds. The man suffered life threatening injuries, police said, and was transported from the Whittier Street Apartments complex to Brigham and Women's Hospital, where he later died.

Officers responded to Columbia Rd. and Washington St. in Dorchester at 2:03 p.m., where they found two victims suffering from gunshot wounds. The victims, one with life threatening injuries, were transported to Brigham and Women's Hospital and Beth Israel Deaconess Medical Center. A man in his 20s died later Thursday, while the other was treated for non-life threatening injuries.

The Dorchester shooting took place in the Burger King parking lot, next to the Jeremiah E. Burke High School, near the school's dismissal time. Burger King's parking lot and drive-through entrance were fenced off with police tape.

Police are investigating both shootings.

Schools near both scenes were put into "safe mode" after the shootings, Boston Public School officials said. During that time, no one could enter or exit the buildings, but students and staff could move around inside. This incident caused minimal disruption at the Lilla Frederick and UP Academy Holland, where classes were ongoing at the time, according to school officials.

At about 1:50 p.m., Madison Park Technical Vocational High School and O'Bryant School of Mathematics and Science, both on Malcolm X Boulevard, in Roxbury, were placed into safe mode for about 30 minutes due to police activity. This occurred as school was dismissing for the day, and students were told to remain in the building until the safe mode was lifted.

The Burke and Dearborn STEM Academy, located in the same building, were placed into safe mode at about 2:15 p.m., along with the Lilla Frederick Middle School, and UP Academy Holland. The safe mode lasted for about 20 minutes.

This is a developing story.