Canadian comedian Nathan Fielder has started a prank that went viral this week, and it is not making parents too happy.

The Comedy Central host of “Nathan for You” went on Twitter Wednesday, asking people to text their parents the following:

Since then, hundreds of people have tried out the experiment, causing parents to become concerned about their children’s extracurricular activities. The prank has become very popular, with fellow celebrities even congratulating Fielder for the joke.

Comedian and talk show host Jimmy Kimmel tweeted Fielder, “this is a GREAT prank…nicely done.”

Most parents were not laughing about the joke, however, as seen in the text screenshots. Many threatened to ground their children, and all reacted in fear that their child was selling drugs.

Look at some of the funnier interactions below:

Check out more reactions here.