KINSHASA (Reuters) - Pro-independence rebels tried to seize strategic buildings in the Congolese mining hub of Lubumbashi overnight, beheading two policemen and killing a soldier before security forces repelled the incursion, regional authorities said on Saturday. Democratic Republic of Congo’s second-largest city is the capital of the mineral-rich southeastern province of Haut-Katanga, where mining companies such as Ivanhoe and MMG Ltd have concessions. Late on Friday, around 200 Mai-Mai militiamen, armed with guns and machetes, had marched into the city of around 2 million people with the aim of occupying official buildings and the local television station, provincial interior minister Fulbert Kunda said. Two police officers were beheaded and a soldier was shot dead in the stand-off with security forces, who killed 16 rebels as they rebuffed the attack, he said. “At the moment the situation is under control and it has become calm across the whole territory of the city,” Kunda said in a video statement. Mai Mai comprise several armed bands that originally formed to resist two invasions by Rwandan forces in the late 1990s. They have since morphed into a variety of ethnic-based militia, including hardline secessionists.