French ground operations began overnight in Mali, said Adm. Edouard Guillaud, the French military chief of staff. France's defence minister said soldiers were headed away from the relative safety of the capital toward the rebel strongholds in the north of the West African former French colony.
Five days of airstrikes have done little to erode the Islamist gains, which some in the West fear could turn the region into a launching pad for terrorist attacks.
The ground assault reversed France's earlier insistence that it would provide only air and logistical support for a military intervention led by African troops.
"Now we're on the ground," Guillaud said. "We will be in direct combat within hours."
On Tuesday, France announced it was increasing the number of troops from 800 to 2,500. The offensive was to have been led by thousands of African troops pledged by Mali's neighbours, but they have yet to arrive, making it increasingly apparent that France will be leading the attack rather than playing a supporting role.
A French military spokesman said Tuesday the Islamists had managed to seize more territory despite the air assault because the fighters were embedding themselves with the population, making it difficult to bomb without causing civilian casualties. He spoke on condition of anonymity in keeping with military protocol.
Guillaud said the militant groups had a history of taking human shields and France would do its utmost to make sure civilians were not wrongly targeted.
"When in doubt, we will not fire," he said.
Supplies for the French forces arrived in a steady stream Tuesday, part of the enormous logistics operation needed to support thousands of troops in the baking Sahara sun, a terrain the Islamists have operated in for nearly a decade. Transport planes bringing military hardware landed in quick succession on the short airstrip: A giant Antonov, two C-17 Boeings and a C-160 disgorged equipment in preparation for a land offensive to try to seize back the northern territory held since April by a trio of rebel groups affiliated with al-Qaida.
Burly French troops in fatigues carried boxes of munitions as armoured personnel carriers lined up at the airport's gasoline pump. Roughly 40 armoured vehicles were driven in overnight by French soldiers stationed in Ivory Coast. They include the ERC-90, a six-wheeled vehicle mounted with a 90mm cannon. Dozens of French Marines camped out on the cement floor of an airport hangar.
Although at least 13 countries have offered support to the Mali mission, only France so far has soldiers there. On Tuesday, U.S. Defence Secretary Leon Panetta reiterated the Obama administration's position, saying no American troops will be sent. The U.S. is helping with communications and intelligence-gathering, and may allow American aircraft to help with transport.
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