Why didn’t the seismic alert sound on cell phones this Monday, May 4? Authorities explained the reason and confirmed that the alert system is now active again.
On the morning of Monday, May 4, at exactly 9:19 a.m., a 5.6-magnitude earthquake occurred with its epicenter 24 km west of Pinotepa Nacional, Oaxaca, according to information from the National Seismological Service.
As a result, the seismic alert was activated in Mexico City via loudspeakers; however, the alert on cell phones did not sound. It is worth noting that this alert system has been in operation since September 19, 2025, when it sounded for the first time as part of a national drill.
Why didn’t the seismic alert on cell phones go off during the May 4 earthquake?
In a statement, the Agency for Digital Transformation and Telecommunications explained that at the time of the earthquake, the cell phone alert system was undergoing maintenance and testing in preparation for the First National Drill, which will take place on Wednesday, May 6.
“Technical tests were carried out in conjunction with the National Civil Protection Coordination, which have now concluded, and the alert system (Cell Broadcast) is once again operational,” the document states.
This Wednesday, May 6, at 11:00 a.m., the seismic alert will sound again as part of the First National Drill. Remember to participate in this exercise and follow Civil Protection instructions at all times.
The last earthquake drill scheduled for this year will take place on September 19 in commemoration of the earthquakes that occurred in 1985 and 2017.
