A hand grenade was thrown outside Greek TV station Skai but did not explode, police said on Sunday, as people voted in the parliamentary election.

"According to the guard of the station it was thrown by two persons riding a motorbike, it did not go off," a police official said. "It is not known if it is a real grenade or a fake but no one is going near."

Bomb disposal experts were on their way to the scene.

Meanwhile, Greeks expressed their fears for the future after casting their ballots in an election that could decide whether their heavily indebted country remains in the eurozone or heads for the exit, potentially unleashing shocks that could break up the single currency.

Read our latest news story here: Greeks go to polls on euro's day of destiny