Claudio Eva, who was sentenced on Monday along with five other scientists and a government official over the earthquake in 2009 that killed more than 300 people and levelled the city of L'Aquila, said the verdict was an "eye for an eye".

The ruling by a court in the shattered city, which defied the commonly held view that earthquakes cannot be predicted, has prompted outrage from the world's scientific community.

"It was a very Italian and medieval decision," said Eva, 74, who added he had received messages of support from colleagues in the UK, elsewhere in Europe and the US. "The judge was local, the prosecutor was local and the public were local – which judge would not have been persuaded by the atmosphere?" he told the Guardian.

Fellow expert Enzo Boschi – also sentenced – who was head of Italy's national geology and volcanology institute in 2009, compared himself to Galileo, the Italian scientist who was tried by the Vatican in 1633 for claiming the Earth revolved around the sun.

On Tuesday, Luciano Maiani, head of the Italian commission that monitors seismic risk, resigned, saying: "I don't see the conditions are there for working serenely." His deputy also quit.