By Yassin Kombi and Sonia Rolley GOMA, Democratic Republic of Congo (Reuters) - Rwandan-backed rebels strengthened their control over east Congo's largest city, Goma, on Wednesday as columns of Romanian mercenaries hired to fight for Congo entered Rwanda under tight supervision by Rwandan security forces.

After the fall of Goma, Rwanda-backed M23 rebels are now marching towards Bukavu in DR Congo's South Kivu. The militia is aiming for the capture of capital Kinshasa city next, as per reports. The M23 rebels began their invasion of DR Congo and stormed Goma on Sunday.

Rwanda-backed fighters controlled most of the besieged DR Congo city of Goma on Wednesday as residents slowly emerged from their homes after days of deadly fighting in the key mineral trading hub.The M23 armed group and Rwandan troops have seized the airport and most of the centre and neighbourhoods since marching into the eastern provincial capital on Sunday after a lightning offensive.