The counterculture holiday of “4/20” has been a symbol for pot smokers and people in support of the legalization of marijuana for years. On Saturday afternoon, an estimated 80,000 people gathered in Denver’s Civic Center Park, celebrating the first 4/20 since Colorado legalized the recreational use of marijuana. But the celebration was disrupted after shots were fired in the crowd, wounding three people.

The shooting occurred around 5 p.m., just after the keynote speech of the day ended. The victims did not suffer life-threatening injuries, and the shooter is still unknown.

Seven shots were fired at the event. The unknown assailant shot a man and woman in the leg and also grazed a youth with a bullet.

Police were closely monitoring the event, according to witnesses. Although smoking marijuana in public is still illegal in the state of Colorado, officials were more concerned about public safety – especially after the recent bombing at the Boston marathon.

Marijuana was made legal for recreational use in Colorado in November 2012, after over a million people voted in favor of Amendment 64. Marijuana still remains illegal under federal law.

The drug has been legal for medicinal purposes in Colorado since 2000, and still remains illegal for anyone under 21. The state is still determining other factors in relation to Measure 64, such as the legal THC levels for drivers.

Not everyone was pleased with the pot-friendly event. A group known as Smart Colorado openly rallied against it, making a statement regarding the event.

“These events… will send a clear message to the rest of the nation and the world about what Colorado looks like in the wake of the passage of Amendment 64 last fall,” the group said in the statement. The statement was posted on their website before the shooting occurred.

The group went on to say that the 4/20 rally is encouraging illegal practices. “Do they respect the limitations outlined by Amendment 64, which does not allow public and open consumption of marijuana or the use by anyone under 21 years old?” the group pointed out.

Advocates of the legalization of marijuana point out health benefits the drug may have for people suffering from diseases such as cancer and Crohn’s disease.

Police in Colorado continue to look for the shooter, and have not released any additional information regarding suspects or possible motives.