Police clash with opposition protesters in Congo mining hub

By Aaron Ross LUBUMBASHI, Democratic Republic of Congo (Reuters) - Police in Democratic Republic of Congo's mining hub fired tear gas on Tuesday at opposition supporters brandishing sticks and shovels who were protesting against arrests targeting youth leaders. Political unrest has spread across the country, Africa's top copper producer, as opposition parties accuse President Joseph Kabila of seeking to circumvent a constitutional term limit and hang onto power beyond the end of his current mand