ATHENS, Greece -- Protests against the Greek leftwing government's planned pension reforms expanded Thursday, as farmers clashed with riot police in the city of Thessaloniki, a journalists' strike pulled news bulletins off air and island ferries remained tied up in port.

Police fired tear gas to disperse the protesting farmers, who had tried to break a police cordon. No injuries or arrests were reported.

About 5,000 farmers took part in the protest, using 100 tractors to block access to an agricultural fair in the city centre. Greece's agriculture minister had been due to inaugurate the fair but was forced to cancel.

Farmers are also blocking key highways, angry at the prospect of severe income losses under planned pension and tax reforms. The government's plans have also upset a broad spectrum of professional groups, ranging from lawyers and fishermen to police and physiotherapists.

Greece's eurozone bailout lenders are pressing Athens to overhaul its pension system, which has been hobbled by high unemployment, an aging population and generous deals in the years ahead of the financial crisis.

The 24-hour journalists' strike pulled news bulletins off air, while news websites were not being updated. Friday newspapers are not set to be printed.

Ferries were tied up in port for a second day due to a seamen's strike, while notary publics also walked off the job.

Unions have called a general strike for Feb. 4.