WELLINGTON, New Zealand (AP) - Morning rush-hour traffic slowed to a crawl in most New Zealand cities Friday as truckers snarled highways and streets with thousands of vehicles to protest higher road taxes.

Tens of thousands of commuters took to highways early to beat the road chaos as truckers driving as slow as 1 mph swarmed into more than a dozen city centers and blocked traffic.

In the main city of Auckland, big rigs sounded air horns as crowds of people clapped and waved in support of the protest that gridlocked the city center. Some vehicles carried placards reading "Good things come by Truck."

The move was sparked by the government hiking road-user tax paid by haulers, adding up to $3,000 in annual operating costs to each truck. Trucking companies said the cost would be passed on to consumers through higher charges.

"The aim of the exercise today is to send a message to the Minister of Transport ... and get Joe Public on our side," owner-operator Nigel Boyd told National Radio.

In the capital, Wellington, up to 200 trucks crawled past the nation's Parliament, angrily sounding air horns in protest as they drove by.