Schools were ordered closed and a state of emergency was declared on the Greek island of Kefalonia on Monday after an earthquake damaged homes and injured at least seven people.

Hundreds of the island's residents slept in their cars after a magnitude 5.8 temblor struck near the town of Lixouri on the western Greek island on Sunday, and was followed by dozens of aftershocks as powerful as magnitude 5.2, according to the Institute of Geodynamics in Athens.

Seismologists noted it was too soon to tell whether the Sunday temblor, which the U.S. Geological Survey listed as having a 6.1 magnitude, was the main earthquake or whether a stronger one might strike in the following days.

"We need 48 hours to say with 99 percent certainty that this was the main quake," Thanassis Ganas, head of research at the Athens Geodynamic Institute, said on Skai television. He added, however, that the aftermath of Sunday's temblor appeared to be developing smoothly, and that the multiple aftershocks were normal and expected.

Kefalonia and nearby Zakinthos and Ithaki were devastated by massive earthquakes in 1953, when a 7.2 magnitude quake struck three days after a 6.4 temblor, levelling nearly all the buildings on the islands, killing hundreds of people and injuring thousands. Buildings constructed in the area since then have been constructed to strict anti-seismic specifications.

Ganas said the quakes on Sunday and Monday were not created by the same fault as those of 1953.

Local officials said two ferries were on the way to the island Monday to provide accommodation for residents whose homes were damaged.

"There is damage but thankfully the island withstood" the quake, said Interior Minister Yannis Mihelakis, who arrived on the island shortly after the quake to review damage. Rockslides left some roads on the island shut and many homes and stores have suffered cracks and broken windows.

Earthquakes are common throughout Greece, but the vast majority are small and cause no injuries or damage.