Mr Ahmed was taken away by security personnel immediately after his speech.
The first prime minister in modern Ethiopia from the country's largest ethnic group the Oromo, Abiy has announced major reforms such as liberalising the economy and pushing for a rapprochement with neighbour and arch-enemy Eritrea.
Prime Minister Abiy Ahmed was in the central Meskel Square to deliver a speech - but not long after he finished, a deadly blast unraveled the crowd.
The sound of the live broadcast on state television cut after the blast, and people in the crowd could be seen craning their heads in the direction of the sound.
An AP reporter saw more than a dozen injured people, the report said. "We did not sign a deal with Ethiopia", said Kheire, " After the visit of Ethiopian Prime Minister, we jointly issued a communiqué on creation cooperation between the two countries and to allow them (Ethiopia) to use our ports".
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It proved the only goal of an entertaining match, although Iran saw one attempt chalked off for offside with help of the VAR. Spain and Portugal are tied at the top of Group B with four points each, one more than Iran .
In another of Abiy's major policy shifts, the prime minister has said Ethiopia will open its state-run telecoms monopoly and state-owned Ethiopian Airlines [ETHA.UL] to private domestic and foreign investment, loosening the government's grip. He said no one was killed, despite earlier statements by the authorities indicating several deaths.
The rally was being held in support of the 41-year-old leader, who took office in April. Ethiopians said they could hardly keep up with the pace of change.
"I've never thought this day will come in Ethiopia".
He urged Prime Minister Abiy to continue with his task of uniting the Ethiopians and make the country stable so as to sustain economic growth.
The movement said its goal was "the realization of a national political system in which government power and political authority is assumed through peaceful and democratic process based on the free will and choice of citizens of the country". And the Tigrayan People's Liberation Front, a party in Ethiopia's ruling coalition that has been the dominant force in government for most of the past 27 years, said the announcement on the peace deal had been made before the ruling coalition's congress met to discuss it.
Ethiopian Prime Minister Hailemariam Desalegn resigned unexpectedly in February, saying he hoped to end years of unrest and political upheaval.