Colombia's President Juan Manuel Santos has been sworn in for a second term of four years amid a renewed wave of rebel violence that has put peace talks at risk. The 62-year-old economist has promised to end the country's 50-year-old conflict with FARC rebels, but recent attacks have ignited tensions. The conflict has killed more than 220,000 people and caused more than five million to flee their homes. Al Jazeera's Alessandro Rampietti reports from Bogota. Subscribe to our channel http://bit.ly/AJSubscribe Follow us on Twitter https://twitter.com/AJEnglish Find us on Facebook https://www.facebook.com/aljazeera Check our website: http://www.aljazeera.com/