Yard-high fences were being erected along the route where 80 runners will carry the torch through the Australian capital on Thursday.
Hundreds of police will guard the torch in Canberra to prevent the type of interruptions that have plagued the relay in cities including Paris and London during its global march toward the Beijing Olympics in August.
Protests over China's human rights record and its crackdown on anti-government activists in Tibet have turned this year's event into one of the most contentious in recent history. Many countries, including Australia, have responded by modifying routes and boosting security.
Police in Canberra sought to end lingering confusion about the role of Chinese security agents in the relay, with police chief Mike Phelan saying three Chinese "flame attendants" will always be near the torch but will have no official security role.
The blue-clad Chinese officials became notorious following claims they acted like thugs during chaotic protest scenes in London earlier this month.
Chinese ambassador to Australia Zhang Junsai told Channel Nine television news Tuesday that Chinese security officials may intervene, saying: "If the flame is attacked I believe they will use their body."
However, Australian officials said Wednesday that they had sorted out some communication issues between themselves and Chinese officials.
"All security will rest with us," Phelan said. "I don't know if I can be any clearer than that."
The flame arrived at an air base in Canberra from Indonesia and was greeted by government and Olympic officials and Aboriginal elder Agnes Shea, who said she hoped the torch's stay would symbolize "good will for all mankind."
Officials said the flame's location was being kept secret between its arrival and the relay Thursday because of the threat of protests.
"I don't know, and I don't want to know," Australian relay organizer Ted Quinlan told reporters. "Originally, it was going to a hotel but there's a distinct possibility it's going to go to the embassy."
Torch bearer Lin Hatfield-Dodds withdrew from the rally Tuesday, saying the symbolism of the relay had changed after China's Tibet crackdown last month.
Other torch bearers said the Olympics were the wrong place to make political protests. Ian Thorpe, a five-time Olympic gold medalist swimmer who will carry the torch Thursday, said the protests "shouldn't be centered around a specific event."
Tibetan protests were expected Thursday, as well as pro-Chinese rallies. Both sides say they want the event to be peaceful.
Quinlan said he expected "a lot of noise" during the relay, which will thread along a 10-mile route that passes Parliament House and within 200 yards of the Chinese Embassy.
Australian police have been given special powers authorizing them to stop and search people for prohibited items such as eggs and paint bombs.
Australian Prime Minister Kevin Rudd has said police will "come down like a ton of bricks" on anyone who behaves violently or unlawfully during the relay.
After Australia, the flame will head to Nagano, Japan, where the relay has already run into problems. Officials at a historic Buddhist temple changed their minds about hosting the flame because of security concerns and unease among its monks and supporters over China's treatment of Buddhists in Tibet.
Would-Be Anti-China Protester Expelled From Mt. Everest
Nepalese authorities forced a Western climber caught with a "Free-Tibet" banner to end his climb of Mount Everest, about a week before a planned ascent by Chinese climbers carrying the Olympic torch, officials said Wednesday.
The climber, whose identity has not been released, was caught with the banner in his bags at Everest's base camp, said mountaineering officials in Nepal's capital, Katmandu. The officials did not want to be named because they are not authorized to speak to reporters.
The climber is the first to be stopped by soldiers and policemen stationed on the Nepalese side of the world's highest mountain to prevent anti-China protests during the planned torch run to the summit.
The climb, which is expected to start some time next week, will take place on the Chinese side of the mountain. But the Nepalese government, complying to pressure from Chinese government, has posted soldiers on the southern side and banned climbing near the summit between May 1-10 as a precaution.
Police and soldiers have been given orders to stop any protest on the mountain using whatever means necessary, including use of weapons, but the use of deadly force is authorized only as a last resort.
There are already dozens of mountaineers on Everest for the popular spring climbing season. Climbers spend weeks acclimatizing before attempting the 29,035-foot summit.
They will be barred from going above Camp 2 at 21,300 feet until the Chinese finish their torch run. The harsh weather on Everest usually allows only two windows of time in May - anywhere from a couple of days to a week - when conditions are favorable enough for the push to the summit.