The most recent incident was Wednesday at Nassau Community College in East Garden City.
At the building at 1 Education Drive, a security officer discovered three swastikas on a stair hand rail and on the wall. The swastikas were about 8 inches long and were in black ink.
There have been three other "bias incidents" at the college, according to the Nassau County Police Department:
-- Oct. 15: At 8:44 a.m., three swastikas were found inside the E Cluster Building's second floor men's bathroom. They were drawn using a green magic marker.
-- Oct. 28: At 9:52 p.m., the cleaning staff discovered two swastikas and an anti-semitic comment on the wall of the men's bathroom in the Cluster D Building.
-- Oct. 29: At 12:40 p.m., security discovered multiple swastikas drawn in blue marker randomly placed on the walls and urinals in both men's rooms on the first and second floors of the E Building.
Anyone with information on the case is asked to call 1-800-244-TIPS.