GAITHERSBURG, Md. (DC News Now) -- Police in Montgomery County arrested a person who is accused of crashing into a man riding a lawn mower and killing him in August. The Montgomery County Department of Police (MCPD) said Maxim Galkin, 24, was arrested and charged with gross negligence manslaughter by a vehicle on Tuesday. On Aug. 20, first responders were called to the Great Seneca Highway and High Gables Drive area for a report of a crash between a black 2021 Genesis G70 and a riding lawn mower. 9 people hurt, 1 dead in shooting, fiery crash near Towson funeral home, police say Juan Guerrero-Moreno, 28, was found lying in the roadway. He was taken to the hospital with serious injuries. He died there. An investigation found that Galkin was driving around 100 mph in a 50 mph zone. There were yellow pedestrian warning signs at an intersection and MCPD said despite that, Galkin's sedan hit Guerrero-Moreno in the riding lawnmower while he was crossing Great Seneca Highway's northbound lanes from west to east. Galkin stayed at the scene of the crash. He was taken to the Montgomery County Central Processing Unit and released on a $100,000 unsecured personal bond.