Ethiopians react after an explosion during a rally in support of the new Prime Minister Abiy Ahmed in Addis Ababa, Ethiopia June 23, 2018. REUTERS/Stringer

NAIROBI (Reuters) - An Ethiopian court has freed 11 police officers on bail after they were detained on suspicion of negligence in a grenade attack on a rally in June attended by Prime Minister Abiy Ahmed, state-affiliated media said on Tuesday.

The attack in the capital Addis Ababa on June 23 injured more than 150 and raised fears that a group or individual may want to use violence against Abiy, who has presided over a series of reforms and a rapprochement with Eritrea since taking power in April. [nL8N1TQ0A3]

Among those freed on bail is the former deputy commissioner of Addis Ababa police commission Girma Kassa, Fana Broadcasting Corporation said. None of the police have been charged.

Earlier this month, Ethiopian federal prosecutors said they had charged five suspects with involvement in the incident, including a man released from prison under a government amnesty, but did not elaborate on the motive for the attack.[L5N1UU2P8]