The incident happened at Eisenhower Park in East Meadow at about 11 a.m. on Saturday, July 30, according to the Nassau County Police Department.
A Nassau County worker discovered that a suspect or suspects used a marker to draw a swastika on the trailer, which was located on Park Boulevard between ballfield 14 and 15, police said.
Detectives asked anyone with information about the case to call Nassau County Police Crime Stoppers at 1-800-244-TIPS.
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