The army in the Democratic Republic of Congo on Tuesday pursued an offensive against rebels of the M23 movement to protect the North Kivu provincial capital of Goma, military sources said. Colonel Mamadou Mbala, head of commando forces in the regular army (FARDC), told AFP by telephone that his troops were ordered to place Goma \"out of danger\". The city is key to a region rich in minerals including gold and coltan, a key component in cell phones and other electronic equipment. M23, a movement launched by Tutsi defectors from the army who accuse the Kinshasa government of reneging on a 2009 peace deal, last year occupied Goma for 10 days before pulling out under international pressure. An AFP photographer arrived in the morning at Kanyarucinya, a town 15 kilometres (nine miles) from Goma, and reported a heavy army presence, but no clashes. However, fighting was under way to the north. At Munigi, the first village on the road out of the city, the photographer saw a crowd surrounding two bound men in the hands of government soldiers who were presented as M23 \"spies\". \"M23 is holding its positions in spite of heavy shelling,\" rebel Colonel Youssouf Boneza, commander of M23 operations in the sector, told AFP by telephone. Each side accused the other of starting the fighting on Sunday, and the government has revived an allegation that M23 is receiving support from Rwandan troops in the heaviest clashes in months. \"Our forces have inflicted very heavy losses on the M23 fighters, 120 have been killed and 12 captured,\" for the loss of 10 government soldiers, government spokesman Lambert Mende said Monday. \"For several weeks the M23 rebels and their Rwandan allies have been reinforcing their positions,\" he said. Neighbouring Rwanda, as well as Uganda, strongly reject all charges of support for M23. Casualty figures could not be independently verified. The army was keeping journalists away from the battle zone and M23 has so far issued no toll.