Police say don't use *77 to block robocalls on your cellphone. You'll reach 911 instead

Corrections & Clarifications: An earlier version of this story was written based on outdated information.

Do not call *77. That's the all-caps message the Massachusetts State 911 Department wants to get out quickly to cellphone users in the state. 

"*77 is a vestige of a much earlier version of a way to connect to state police in MA.," wrote Felix Browne, the communication director for Massachusetts' Executive Office of Public Safety and Security, in an email to USA TODAY. "Some carriers now block it and it is not the right number to use for emergencies."

This comes after a recent column from USA TODAY contributor Kim Komando highlighted effective ways to block those irritating spammy robocalls. 

Unfortunately, that's not all it does. In some states, like Massachusetts, it actually connects to emergency services. And in readers' exuberance to block those pesky robo- and spam calls, many in the state inadvertently flooded 911 call centers with non-emergency calls.

For Sprint customers, *77 in Illinois, Maryland, West Virginia, Rhode Island and Virginia also goes to State Police. For T-Mobile and Verizon customers, *77 results in "call can not be completed." AT&T said *77 is a feature only for landline customers and when tested in California, we got the same "call can not be completed" error message. 

Clicking *77 has "resulted in increased call volume at the public safety answering point...run by the State 911 Department in Framingham," wrote Browne. "The Department works hard to tell the public that 911 is the number to call because it has the most functionality to the dispatcher at the PSAP (such as geolocation) whereas *77 does not provide the same amount of information about the caller to the dispatcher."

Beyond Massachusetts, in Delaware, #77 is listed on American Automobile Association's website as reaching emergency dispatch, while other number combinations for cell service include *47 in Alabama, *273 in Alaska and *277 in Colorado. 

More: How to stop robocalls, block numbers on your iPhone, Android and even landline

More:The U.S. received 26.3 billion robocalls in 2018, report

More:How cellphone companies will help you thwart robocalls

AAA has a full list of the number and symbol combinations you might want to avoid on your mobile device since you may unexpectedly reach 911 instead. 

To reiterate, the primary way to reach out for emergency services is by dialing 911.