Three coal trains bound for Carrington Coal Terminal were halted for about six hours when protesters chained themselves to the carriages. To date the protest has resulted in 53 arrests, New South Wales police told International Longwall News this morning.

The trains, scheduled to deliver 20,000 tonnes of coal, were delayed but port operator Port Waratah Coal Services said ship loading operations had not been affected.

More than 1000 protesters turned up for the train blockade – part of environmental group Camp for Climate Change's six-day protest against the coal industry.

More action followed this morning when demonstrators chained themselves to a coal loader at the Kooragang coal terminal, resulting in five arrests.

Port Waratah Coal Services spokesman Graham Davidson told News Limited coal loading was brought to a standstill for more than two hours this morning.

Police said no more protests were planned.

Bloomberg reported prices for thermal coal at Newcastle hit a record high at the beginning of the month due to rising demand and constraints on supply.

Xstrata, BHP Billiton and Rio Tinto all ship their coal through Newcastle.