Greek police clashed with dozens of immigrants at the western port of Patras on Tuesday in the latest violence to hit the country's conservative government since riots in December.

Police said a passerby and a policeman were injured in the violence that broke out after an immigrant tried to hide on a truck boarding a ferry to Italy and got hurt in the attempt.

Greece's Patras port is a gathering point for hundreds of migrants from the Middle East, East Africa and Central Asia hoping to stow away aboard ferries bound for Italy, where they believe they have a better chance of receiving asylum.

"The immigrant got trapped under the truck and was injured," a police official said on condition of anonymity. "About 70 other immigrants attacked the driver and clashed with police."

Greece is struggling to cope with a rising number of migrants swamping its long coastline and border with Turkey.

Last month, truck drivers staged protests at Greek ports and border crossings, demanding measures to deal with illegal immigrants destroying goods and fighting drivers in efforts to stow away. The government pledged to start talks soon.

It was the second time this year border crossings were blocked by protesters. In January, angry farmers demanding better prices for their products blocked roads and crossings with Bulgaria but with ended the blockades after promises of a half-billion euro aid package.

Since the fatal police shooting of a teenager in December which triggered the country's worst riots in decades fuelled by anger at economic hardships, a wave of violence has put pressure on the government clinging to a one-seat parliamentary majority.

Police said late on Monday more than ten people wearing masks attacked a train in a northern Athens suburb dousing six carriages with gasoline and then throwing firebombs. No injuries were reported.