A terrible thunderstorm struck the Zagreb area around 2 a.m. tonight, keeping many people up and causing a sleepless night. One Twitter user wrote that it was “like an apocalypse” while another said he did not expect thunder to wake him up at 3 in the morning.

The storm was caused by announced changes in weather and cyclones that moved over the area, bringing with them thunder with strong shocks. According to Dunja Plačko Vršnak from DHMZ, the weather is appropriate for this time of year. The strength of the thunder was also evident from an EMSC tweet, as many people thought it was an earthquake due to its intensity and shaking sound heard in the northern part of Zagreb.

One Facebook user described his experience as “rumbling, slightly shaking” while another user from Stenjevac added that he heard a strong sound during the storm. Overall, it was a tumultuous night for those in the Zagreb area who were caught off guard by this sudden turn of events.