Buenos Aires - The Olympic torch relay escaped major incidents Friday in Buenos Aires, with the flame covering almost 14 kilometres through city streets amid very tight security.

Under a grey sky, Argentine windsurfer and sailor Carlos Espinola - a triple Olympic medalist - was first to carry the torch among a total of 80 people over more than two hours, ending with former tennis star and Olympic silver medalist Gabriela Sabatini.

No incidents of any significance were reported during the relay, although one spectator threw a water balloon as the Olympic torch passed by the historic Plaza de Mayo, in the hands of equestrian Lucas Werthein.

The water balloon was intercepted by the abundant security personnel who accompanied the Olympic symbol amid the crowd.

Some "Free Tibet" signs were seen along the way, but there was no violence and no serious disruption of the torch relay.

Minutes before carrying the torch, Sabatini told television that the moment was of great importance for Argentine sport, and called for political issues to be debated away from sport.

"We should not cast a shadow on this celebration, which is the celebration of sport," Sabatini said.

The relay was preceded by a tango-inspired show from Argentine classical dancer Inaki Urlezaga and a warm welcome from Buenos Aires Mayor Mauricio Macri.

"The Olympics are a time for brotherhood and coexistence. We hope the party that is about to start heads in that direction. We hope to meet expectations," Macri said.

Another show - featuring well-known popular singers - was to mark the end of the Argentine leg of the Olympic relay at the Argentine capital's Equestrian Club.

Argentine football legend Maradona declined to carry the torch due to commitments in Mexico, but other current and former stars participated both on dry land and on rowboats on the river.

A few scores of demonstrators identified with the Falun Gong spiritual movement carried an alternative "human rights torch" to the presidential palace, demanding a boycott of the Beijing Olympics scheduled in August.

Many members of the Chinese community who reside in Argentina, however, demonstrated in turn with red flags in favour of holding the Games in their home country.

Argentine authorities mobilized 1,200 federal police agents and 1,500 naval police officers alongside some 3,000 civilian stewards to prevent incidents during the relay and avoid the violence that has plagued the Olympic symbol at other stages on its way to Beijing 2008.

The Olympic flame arrived Thursday in Buenos Aires from San Francisco for the torch relay's only South American stop ahead of Beijing 2008, and the first-ever Olympic torch relay stop in the Argentine capital.

After protesters hounded the Beijing-bound flame for the last week across Europe and during its sole North American leg Wednesday in San Francisco, there were no demonstrators at the airport as the torch arrived in Argentina.

The torch was brought into the airport through areas off limits to the public, with a heavy police escort.

Buenos Aires was the seventh leg of a very controversial international relay set to go next to Dar Es Salaam, in Tanzania. (dpa)