Chilean government defends motor-sport rally as archaeologists say nearly half of ancient sites on 10,000km route are damaged

The Dakar Rally of 500 off-road vehicles bumping and skidding through clouds of dust may be one of the world of motor sport's most spectacular sights but archaeologists, environmentalists and indigenous groups are warning the 14-day event is ruining Chile's ancient heritage.

Chilean government studies seen by the Guardian confirm the damage done to geoglyphs, protected sites, burial grounds and tracks on the Inca trail during previous races, but such is the race's importance for tourism that it has once again been given the green light.

From 5 to 18 January, the latest 6,000-mile (10,000km) rally takes the drivers from Rosario in Argentina to Valparaíso in Chile, via the Andes, Bolivia's salt flats and the Atacama desert.

It has been challenged in the courts and on the streets by critics, who say Chile is paying too high a price to accommodate rich foreign adrenaline junkies, carmakers and their sponsors.

Chile's Archaeologists Association and other conservationist and indigenous groups failed in a legal bid to block the race on environmental grounds. The constitutional court said there was insufficient evidence that the event violated the right to an uncontaminated environment.

This week, troops and police broke up a protest by the indigenous Kolla community, who blocked roads into land they claim as their own in Rumi Cruz.

The Kolla denounced the actions of the government and the race organisers, saying the Dakar Rally aimed to "turn their communities and landscapes into a million-dollar tourist attraction aimed at a rich minority".

Chile's sports minister, Gabriel Ruiz-Tagle, rejected the claims, saying the rally was the only sporting competition with comprehensive environmental protection.

But conservationists have posted images purportedly showing that cars and motorbikes have driven across archaeological digs, leaving tyre tracks over ancient symbols, and scattered and smashing ceramic fragments.

A study by the government's Council of National Monuments on the impact of an earlier race in 2011 revealed that the event affected 44.5% of the 283 protected historical sites that it evaluated.

It lists damage to geoglyphs, villages, cemeteries, middens and lithic or stone-tool workshops in the regions of Tarapacá, Antofagasta, Atacama and Coquimbo. Among the worst-affected archeological archaeological sites was a former fishing village in Coquimbo that may date from 2000BC, in which 50% of the area was degraded.

In 2009-10, the council put the damage at 350m pesos (£400,000) but they received only a ninth of this amount in compensation from the sports ministry. More damage has been done since.

Paola González, vice-president of the Archaeology Association of Chile, said: "The big problem is that public bodies that should be taking measures to protect the sites are unable to intervene, given that this other major public body [National Sports Institute of Chile] is supporting the event.

"The interests of the international company are overriding Chile's legal standards that supposedly exist for the protection of the country's archaeological monuments."

The race organisers have promised to mitigate the impact by marking historical sites on drivers' maps, installing temporary fencing and obliging cars to pass more checkpoints so they are less likely to get lost. But the government's report notes the difficulty of monitoring a race that covers such a wide area with participants – including some amateurs – who are under time pressure to find short cuts.

This is not the first dispute caused by the Dakar Rally, which started in 1978. When it was held in Africa, locals complained of high costs – including fatal road accidents, roadkill of livestock, and dust – but little benefit, except to high-end businesses. The Vatican City newspaper L'Osservatore Romano described the race a "vulgar display of power and wealth in places where men continue to die from hunger and thirst".

The race was moved to South America in 2009, after threats from al-Qaida forced the abandonment of the previous year's event. It continued to draw controversy and enthusiastic crowds, despite the deaths of several local people in collisions with Dakar Rally vehicles. Environmentalists warn that the chunky, off-road wheels are chewing up the topsoil in fragile highland ecosystems and disturbing some of the last wild habitats of llamas, condors and vicuñas.

French environmentalists and anti-race campaigners have also slammed the race, most notably in a song by Renaud entitled 500 Connards Sur la Ligne de Départ (500 Arseholes at the Starting Line).