Police and sheriff's deputies searched stores suspected of selling an especially dangerous form of synthetic marijuana after 33 people apparently overdosed on the drug in one Brooklyn neighborhood. Michael Herzenberg filed the following report.

Law enforcement swooped into five businesses in Bedford-Stuyvesant on Wednesday looking for K2, synthetic marijuana. They didn't find any, but the sheriff's office uncovered untaxed cigarettes at three bodegas and arrested three people.

When NY1 visited this neighborhood earlier in the day, we found stumbling people bracing to hold themselves up at the corner of Myrtle Avenue and Broadway. Some residents call it Zombieland.

"It's pretty normal. Try to stay away from it," said one resident.

"This area was worse, but now, it's gotten worser," said another.

The enforcement crackdown came a day after 33 people in the neighborhood were hospitalized for suspected K2 overdoses.

A nurse at Woodhull Medical Center says staff scrambled to respond.

"All of a sudden, it's like they all came in together. Stretchers upon stretchers, ambulance upon ambulance," said Doris Benjamin, a registered nurse at Woodhull Medical Center. "Most of them were very drowsy and lethargic."

One of the biggest challenges was pinpointing the kind of synthetic marijuana involved.

"We're talking about hundreds of different types of compounds that might be in there," said Dr. Robert Chin, chief of the emergency department at Woodhull Medical Center.

“As you know, there are lots and lots of forms of K2," said Mayor Bill de Blasio. "This one was one was a very bad, a dangerous one, that people didn’t know before and were trying, and it had really horrible effects."

At a news conference, the mayor vowed that his administration would use new laws to "throw the book at anyone selling K2."

“NYPD is very focused on it," de Blasio said. "I talked to the leadership in Brooklyn from the neighborhood affected by this. You’re going to be seeing very vigorous enforcement, very quickly.”

State lawmakers last year made possession and sale of the drug illegal, and the City Council made it easier to close stores that have the drug. But the Brooklyn borough president says about two weeks ago, synthetic marijuana re-emerged as a problem in this neighborhood.

The mayor said while stepped-up enforcement is important, so is educating young people about the dangers of K2.