HONG KONG, China (CNN) -- Hong Kong prepared Friday to stage the Olympic torch relay, the first time the event will be held on the soil of the host of this year's Summer Games.
The Olympic flame arrives from Vietnam at Hong Kong's international airport Wednesday.
Gray skies, light rain and heavy mist greeted the thousands of organizers and police who were deploying across the region, as the torch was to be carried through canyons of skyscrapers and outlying communities in the New Territories.
Hong Kong residents have been encouraged to wear red to show their support for the flame, and about 3,000 police will be on hand.
What remained to be seen, however, was the level of any protests that may happen in Hong Kong. The special administrative region is a place with civil liberties unrivaled in the rest of China.
Hong Kong was a British colony until the city was handed back to China in 1997. Although Beijing makes all the big political decisions, Hong Kong was promised a wide degree of autonomy under a formula called "one country, two systems."
The media are allowed to criticize the leaders, massive street protests have been held demanding greater democracy, and English is still the official language in the courts, where judges wear British-style wigs.
For Friday's event in Hong Kong, protesters have said they would wear orange -- a mixing of the Chinese symbolic colors of red for the country, and yellow for freedom. Watch more about Hong Kong's preparations »
But for special events such as the Olympic torch relay, Hong Kong leans more toward the "one country" part of the formula than the "two systems" part. In the past week, authorities used a blacklist to stop seven pro-Tibet and human rights activists at the airport. After questioning, they were deported.
On Wednesday, the protest-plagued Olympic torch relay arrived in Hong Kong, its first stop on Chinese soil.
Authorities in Hong Kong deported at least seven activists before the flame's arrival and braced for possible protests and the arrival of more activists prior to the official torch run on Friday.
The flame arrived at 2 p.m. (6 a.m. GMT) with red-carpet treatment at Hong Kong International airport, greeted by a row of children waving Chinese flags and a band playing patriotic tunes.
The occasion also marked the 100-day countdown to the start of the Beijing Olympic Games, which begin on August 8.
Authorities plan to deploy 3,000 officers to guard the flame, according to media accounts.
Demonstrators criticizing Beijing's human rights record and its recent crackdown in Tibet dogged the relay in London, England; Paris, France; and San Francisco, California.
However, the flame had protest-free jaunts in Pyongyang, North Korea, on Monday and Ho Chi Minh City, Vietnam, on Tuesday -- the last stop in a 29-day odyssey through 21 cities in five continents before entering China. Watch as China celebrates the 100-day mark to the Olympics »
The torch relay also will stop in Macau before heading to the mainland, including Tibet, where Chinese authorities cracked down after violent riots broke out against Han Chinese there in March.
There sometime in May weather-permitting, Chinese climbers plan to take the Olympic flame to the summit of Mount Everest, the world's highest peak at 29,028 feet (8,848 meters). Watch a journalist currently following an Olympic flame at Everest »
Since its handover to China by the British in 1997, Hong Kong has been allowed to run its own domestic affairs with considerable autonomy until 2047.
The territory grants visa-free entry to many Westerners, raising the possibility that the relay Friday could be greeted with the kind of protests it has faced in some other stops.
However, three pro-Tibet campaigners and a freedom of speech activist were barred entry into Hong Kong and questioned for hours at the airport before being deported, according to Students for a Free Tibet's web site.
The trio involved two of its members and an organizer with the Free Tibet Campaign. Their plan was to take part in a press conference that would draw attention to the likelihood of violent protests, if China did not cancel the "provocative" Tibet leg of the torch relay.
"The Chinese government has shut out international observers and media from Tibet, and now they have even stopped individuals from speaking out in Hong Kong about the humanitarian crisis unfolding in Tibet," said Kate Woznow, campaign director for Students for a Free Tibet.
China says 18 civilians and a police officer were killed in Lhasa during the March violence. Tibetan exile groups say many times that number were killed in the ensuing crackdown.
Also deported Tuesday was free speech activist Zhang Yu, who was flying in to take part in "World Press Freedom Day." The four-day conference calls for freedom of expression in China.
He was detained for seven hours before being deported, the Hong Kong Journalists Association said.
Authorities did not specify a reason for barring his entry, said the association's general secretary, Mak Yin-ting.
Danish sculptor Jens Galschiot and two others were detained and deported on Saturday while trying to participate in the same conference, Mak added.
"Jens was coming here to promote the freedom of expression, but he himself was deprived of the freedom of expression," Mak said. "The Chinese government pledged to have a free press if it could host the games. We urge the Chinese government to do it."
Galschiot created "The Pillar of Shame," a sculpture in Hong Kong depicting 50 torn and twisted bodies to symbolize those who died in the 1989 Chinese crackdown at Beijing's Tiananmen Square.
Actress Mia Farrow planned to fly in on Thursday to raise awareness about the fighting in Sudan's Darfur region, where an estimated 300,000 people have been killed and 2.5 million others displaced. She will call for China to press Sudan to let more U.N. peacekeepers in to Darfur.
China is believed to have special influence with the Islamic regime because it buys two-thirds of Sudan's oil exports and sells weapons to Sudan. China also defends Khartoum in the U.N. Security Council.
Nepal, meanwhile, deported a U.S. citizen on Tuesday for allegedly holding a "Free Tibet" banner on Mount Everest.
Even though the climb up Everest will take place on the Chinese side of the mountain, Nepal has posted about 25 security personnel on its side of the mountain -- an attempt to maintain good relations with its neighbor. Nepal has granted them permission to shoot mountaineers engaged in anti-Chinese activities, according to a Home Ministry official. E-mail to a friend
CNN's Saeed Ahmed contributed to this report
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