Update, 10:56 a.m.: Police have arrested a woman who allegedly fired a gun Monday morning and barricaded herself in a building. Nobody was injured in the incident, authorities said.

Original item: Police and fire personnel are working a barricade situation in Southwest D.C. after a person was reported to have fired a gun and then run into a building Monday morning.

Fire personnel who were on a medical call saw a person fire a gun then run away, officials said. Firefighters called police and reported the incident, police said.

It is unclear if anyone was hit, police said.

The shooting happened about 7:15 a.m. in the unit block of M Street SW. The barricade is in the unit block of N Street SW, police said.

Several streets in the surrounding area are closed, including First Street, Half Street, and M, N and O streets, authorities said.

This item has been updated since it was first published.