Runners carried the Olympic torch through China's capital Wednesday, snarling traffic and prompting both excitement and worry over the city's plans to host the 2008 Olympic Games. Thousands welcomed the flame on another leg of its round-the-world trip to the Athens games in August.

Gunfire on Tiananmen Square followed by applause saluted the Olympic torch as the first runner began a relay through the streets of the capital - all the way from the center to the Summer Palace, an imperial-era resort on the outskirts of the city.

By the time the time it arrives at the site of this year's games in Athens, Olympic committee officials say the torch will have been carried more than 70,00 kilometers to 33 cities on six continents.

Wednesday's ceremonies in Beijing began with a torch-lighting ceremony in Tiananmen Square. Some Beijingers said they were excited and proud that their city will be host the Olympic Games four years from now. But the torch's run-through Wednesday also raised concern about what will come in 2008.

The torch's presence brought a reminder of the traffic jams that many fear could mar the Beijing games. Traffic on some of the capital's main thoroughfares was snarled for hours Wednesday when streets were closed to allow the torch to pass.

With China's economy booming, Beijingers have been purchasing cars at a frantic rate. Chinese economists estimate that about 1,000 new private vehicles are entering the capital's already overburdened streets each day. Tourism officials hope to attract a million visitors to the city for the 2008 games, and analysts say the prospect of traffic paralysis then is a very real threat. Graham Smith is the lead transport specialist with the World Bank office in Beijing. He says the sudden new glut of cars is raising questions about how officials will deal with the situation.

"Are there policies in place to discourage people from using their personal cars, by [imposing] parking charges? Is there good enough public transportation to encourage people to leave their cars at home?" asks Mr. Smith. "In the coming years as we get up to the Olympics in Beijing in 2008, that's going to be a tough one for the mayors to solve."

Beijing officials have vowed to improve local transportation before the games begin. They will be adding several new lines to the subway system and building hundreds of kilometers of new expressways around the city.