In a few minutes 22,000 people notified the EMSC, although the tremor was a weaker aftershock following the main magnitude 6.2 earthquake which struck shortly after noon.
The number of reports of the main earthquake certainly would have been higher, but the lines could not withstand so much traffic, said Remy Bossu, seismologist and leader of a nine-member team whose services have been used by many Croats since the March earthquake in Zagreb.
Many will open the EMSC's Last Quake app as soon as they feel the ground shaking, and in less than 15 seconds they will find out if their senses have deceived them or if it was indeed an earthquake, before seismological institutes even read, let alone publish the location and the magnitude.
The EMSC also detects witness reactions on the Internet before seismologists provide traditional data. To prevent panic-mongers from abusing its information, the EMSC communicates with clients and Croats accept its explanations more and more, the newspaper said.