There’s a prank going around that has owners of Apple Inc.’s (NASDAQ:AAPL) iPhone devices saying “108” to Siri.

Users that say “108” to Siri are actually telling the virtual assistant to call 911. Siri will wait five second before making the call so that the person can cancel. However, some versions of the prank tell the target of it to close their eyes for five seconds before looking to see Siri’s response.

The reason that Siri calls 911 when a person say s”108″ to her has to do with another country’s security code. 108 is India’s version of 911. Apple Inc. has it set up so that the Indian version of 911 can still be used in other countries, reports Daily Mail.

While the prank won’t bring any harm to the person tricked by it, it isn’t a good idea. Calling 911 without an emergency could cause an actual emergency to be delayed. It is also punishable in some states. Maine is one of these states and it could hand out fines and jail time to those abusing the system.

While the current prank focuses on having Siri call 108, there are other numbers that users should look out for. 112, 110, 999, and 000 are all emergency numbers in other parts of the world. Saying any of them to the virtual assistant will also have her calling 911, WGME notes.

If you really feel the need to prank someone with Siri, there are better options. For example, you could set Siri to call the owner of the device by a different name or title. This is sure to catch them off guard and doesn’t risk putting anyone in danger.