By Abdoulaye Massalatchi

NIAMEY, July 4 (Reuters) - Gunmen in northern Niger have attacked the living quarters of a French roadbuilding company, military officials said on Wednesday, the latest such raid in the mineral heartland on the edge of the Sahara desert.

Around 15 armed men attacked the SATOM-SOGEA compound on Tuesday. Two off-road vehicles were stolen but there were no reports of casualties.

The army officials, who asked not to be named, said the attackers were thought to be from the rebel Niger Movement for Justice (MNJ), which is fighting for greater autonomy for the economically marginalised desert region.

But Seydou Kaocen Maiga, an MNJ spokesman based in Paris, said the group was not behind the raid.

"We are not claiming this attack. You know, there are a lot of people active in this zone," he told Reuters.

The incident occurred close to Aderbissinat, south-west of the main northern town of Agadez and more than 1,000 km (620 miles) from the capital Niamey.

Northern Niger is the mineral-rich region of the former French colony, with reserves of uranium, iron ore, silver, platinum and titanium. Yet the country is one of the poorest on earth, languishing near the bottom of most development indices.

Foreign firms from countries including China, France, Canada and India are flocking to the region to mine the riches, particularly uranium, fuelling resentment among parts of the local population who feel they are not seeing the benefit.

Northern Niger has long been a hotbed of dissent, largely beyond government control, full of disenchanted, unemployed youths, and awash with arms left over from an uprising by Tuareg, Arab and Toubou nomads in the 1990s.

The MNJ launched a campaign of attacks in February. Since then it has carried out a series of raids on military targets including Agadez airport. Last month it killed 15 soldiers and took dozens hostage in its boldest strike yet.

Although the group has said it wants greater control over the region's natural wealth, it has said it does not intend directly to attack foreign companies operating in the region.

It accuses government forces of randomly arresting and killing civilians during security clampdowns and says the insecurity which is rife around Agadez is a result of central government's neglect of the region.

President Mamadou Tandja's government refuses to recognise the MNJ and denies talk of a resurgent rebellion, dismissing the attacks on military targets as acts of banditry, despite growing calls from political parties in Niamey for negotiations.

The security forces deny rebel accusations of indiscriminate arrest and say they do not kill innocent civilians.

The MNJ said on its Web site on Tuesday the army had bought new equipment, including Mi-24 attack helicopters, and hired Ukrainian mercenaries to pilot them for an offensive in the desert.

Defence officials in Niamey declined to comment.

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