NEW YORK - The NYPD has released two videos as a warning to New Yorkers about the dangers of synthetic marijuana, which they say is becoming a big problem across the city and the country.

One video was taken in Brooklyn, showing a naked man crouching in front of a van howling while acting violent and delusional. The second video was shot out of state, showing another man naked and violently busting through a wooden fence.

Side effects can include paranoia, agitation and fear, as well as causing the person to become violent. The medical side effects include risk of heart attack or seizures, according to Jacobi Medical Center Dr. Maryann Popiel.

Authorities say it's illegal in the state and is often disguised as potpourri or incense. It's mostly being sold in bodegas for about $5 per bag.

NYPD Commissioner Bill Bratton adds that information about the drug is being handed out to officers to help them deal with its increasing use.