A man who was pushed into the Charles RiverTuesday evening has died, according to State Police. Mitchell Harrison, 26, of Watertown passed away overnight at Brigham and Women’s Hospital. The man charged with pushing him into the water, Lenny Quintero-Flores, 27, of Malden, will now be charged with manslaughter, State Police said in a statement Wednesday.

Flores was held overnight at the Leverett Circle Barracks. He will be arraigned Wednesday in Charlestown District Court.

State Police said the men had reportedly been drinking alcohol on a dock near the Massachusetts Avenue bridge before Harrison, while either sleeping or passed out, was intentionally pushed into the water by Flores shortly before 5 p.m.

Harrison was pulled out of the river about 20 minutes later.

Flores was arrested and initially charged with assault and battery causing serious bodily injury.