A magnitude 6.4 earthquake struck central Croatia on Tuesday, killing seven people, injuring more than 20 and rattling several neighbouring countries.

Rescuers pulled people from the rubble of collapsed buildings in Petrinja and other towns, as army troops were sent to the area to help.

Tremors were also felt in Croatia’s capital Zagreb and as far away as Austria’s capital Vienna. Slovenia shut its only nuclear power plant as a precaution.

It was the second quake to strike the area in two days and aftershocks of magnitude 3.0 and higher were felt throughout the day.

People in Zagreb rushed onto the streets, some of which were strewn with broken roof tiles and other debris.

A day earlier on Monday, a magnitude 5.2 earthquake hit central Croatia, also near Petrinja.

In March, a temblor of magnitude 5.3 rattled Zagreb, causing one death and injuring 27 people.