Dude your in North Dakota a major bee state (ever hear of Souix Bee Honey) if you kill the bees of a beekeeper your state has laws that allow the beekeeper to come after you for damages. ND has some of the strongest beekeeper friendly laws in the nation as beekeeping is a major industry in the northern plains states.
Your best recourse is to contact your Dept of Ag as those same laws require beekeepers to register their apiaries (beeyards) and hives. Try this link and see if there is anything that can help.
http://www.nd.gov/ndda/program/apiarybeesThis section may be what you need.
4-12.2-08.1. Revocation of registration of an apiary.
The agriculture commissioner may cancel the registration of an apiary when the bees
located on the apiary site are causing a nuisance as defined in chapter 42-01.
And here is the definition of nuisance.
42-01-01. Nuisance - Definition.
A nuisance consists in unlawfully doing an act or omitting to perform a duty, which act or
omission:
1. Annoys, injures, or endangers the comfort, repose, health, or safety of others;
2. Offends decency;
3. Unlawfully interferes with, obstructs or tends to obstruct, or renders dangerous for
passage, any lake, navigable river, bay, stream, canal, basin, public park, square,
street, or highway; or
4. In any way renders other persons insecure in life or in the use of property.
Ordinarily I would come down on the side of the beekeeper because let's face it the general public is completely irrational when it comes to bees and wildlife but if your report that he told you that your son can not play in his own yard is true then he needs his butt jacked up around his ears. Beekeepers have to be good neighbors and I hold my own to the same standards I expect from others.
Good Luck