ATHENS (Reuters) - A strong earthquake rocked the island of Cephalonia in western Greece on Sunday but there were no immediate reports of casualties or serious damage, police and fire brigade officials said.

The 5.8-magnitude quake struck at 3.55p, according to the Athens Geodynamic Institute. Its epicentre was 6km north-east of the town of Argostoli, the island's capital. No tsunami warning was issued.

The tremor was felt across western Greece, the Geodynamic Institute said.

"It was a very strong quake and it scared people. So far we have no reports of injuries but there are reports of damage in the road network and in homes, but (it is)... not major," a police official on the Ionian Sea island told Reuters.

Another police official in Athens said eight homes and a few farm houses were reported damaged so far but there were no injuries. Greece's Interior Minister was heading to Cephalonia by helicopter to assess the situation.

"The tremor sent people into the streets and squares; it was quite strong," the police official on the island said.

Greece is prone to earthquakes. Most cause no serious damage, but a 5.9-magnitude quake in 1999 killed 143 people.