If you don't know, Boston has an annual, citywide tradition called Hempfest usually in the fall.
Hempfest is a two-day music and marijuana festival, organized by NORML, held in the middle of the city.
It's a pretty big deal, and many people in Boston are worried that the manhunt for Boston bombing suspect Dzhokhar Tsarnaev would ruin Hempfest and their 4/20 festivities.
Many worried revelers were posting all week on the event's Facebook page. Even though Hempfest isn't ever on 4/20, many seemed to think so.
And as the lockdown was instated over the city by police, many took to Twitter, as well.
Ryan Broderick is a reporter for BuzzFeed News and is based in London.
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