[Cronos]

https://www.worldatlas.com/crime/countries-that-have-produced-the-most-serial-killers.html

Rank	Country	Number of serial killers
1	USA	3615
2	Russia	196
3	UK	190
4	Japan	137
5	South Africa	123
6	India	121
7	Canada	119
8	Italy	97
9	Germany	88
10	Australia	83

And @marktwain --> Mass murder by public shooting is not limited to the United States. -- it is not LIMITED to the USA, but List of countries with the highest numbers of mass shootings in 2023

1. USA 101
2. Russia 21
3. France 8
4. Germany 5
5. Canada 4
6. Finland 3
7. Belgium 2
8. Czechia 2
9. Italia 2
10. Netherlands 2

HOWEVER, 2023-24 Statistical Risk Assessment for Mass Killing has the USA not on the list - though it concerns more terrorist attacks

[MeanWestTexan]

That’s mass murders, not serial killers.

[marktwain]

Your source lists "mass shootings" not mass murder by public shootings. There are several definitions of "mass shootings", but most people think of these things as mass murder, in a public place of unrelated people by shooting. These are often considered "active shooter" events.

Most would not consider the gang execution killing of seven men in the St. Valentine's Day Massacre as a "mass shooting" as it is considered in modern parlance.

From the NCJA: The FBI defines a mass shooting as when one or more people engage in killing or attempting to kill people in a populated area. The bureau’s definition excludes shootings motivated by gang violence, drug violence, domestic disputes or hostage situations, or resulting from another criminal act, like a bank robbery.

In 2022, the FBI found 50 active shooter incidents, of which 13 met the federal definition of a mass killing incident.

The FBI has not released the numbers for 2023 yet.