Deaths from hit-and-run crashes in the United States are now at an all-time high, according to a new study released Thursday by the AAA Foundation for Traffic Safety. 

A crash is generally classified as a hit-and-run when at least one person involved in the incident flees the scene before offering sufficient information or aid to the other parties involved or fails to report the crash.

2,049 people were killed by hit-and-run crashes in 2016 -- a 62% increase from 2009, the last year in which a downward trend was recorded. AAA said the data makes 2016 the deadliest year since the National Highway Traffic Safety Administration began compiling statistics on fatal motor vehicle crashes in 1975.

The new study found that most victims of fatal hit-and-run collisions -- 65% -- were pedestrians or cyclists and that almost 20% of all pedestrian deaths over the last decade were caused by hit-and-run crashes.

The study also found that hit-and-run crashes involving pedestrians are most likely to occur between midnight and 4 a.m., when suspects are more likely to escape unseen; on roads with lower speed limits where pedestrians are most likely to cross, and in areas with heavy foot traffic.