BOULDER, Colo. (CBS4)- Hundreds of students began gathering for the 4/20 rally on the University of Colorado just before 4 p.m. Friday.
Three people were arrested, two for trespassing and one for possession of marijuana.
CU has closed their Boulder campus to visitors to prevent the annual event which attracted thousands to smoke marijuana in public.
Norlin Quad, the traditional place for the 4/20 gathering, was closed this year and monitored by a heavy police presence. Fertilizer was placed on the lawn as an additional deterrent.
In the past, thousands have descended on the quad to light up joints in observance of April 20.
The university is making the campus off limits to everyone who is not a student or staff member.
CU said students who smoke marijuana will be issued a citation.
Just after 4 p.m. students were seen gathering in the quad with signs bearing marijuana leaves and waving Colorado flags.
In the past, thousands have descended on the quad to light up joints in observance of April 20. (See a photo gallery.)
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