Ethiopia's ruling EPRDF coalition on Friday re-elected Prime Minister Abiy Ahmed as its chairman, its chief of staff said, further anchoring the authority of the 42-year-old leader as he pushes through sweeping political and economic reforms. Abiy assumed power in April after his predecessor resigned following three years of unrest. Abiy "will lead the ruling party until the next congress", his chief of staff Fitsum Arega wrote on his Twitter feed. The re-election of Abiy, by a secret ballot at the end of the coalition's three-day congress, was expected. The changes that he has introduced since taking office include making peace with arch-foe Eritrea, freeing political prisoners, pledging to open up the state-controlled economy and promising to overhaul the security services. There has also been a surge in violence along ethnic lines since he came to power, however. *This story has been edited by Ahram Online