An explosion has rocked a rally in support of Ethiopia’s new prime minister, killing one person and injuring 155 others, according to the country's health minister.

The blast occurred as supporters of reformist Prime Minister Abiy Ahmed gathered in Meskel Square in the capital, Addis Ababa. It was heard right after 42-year-old Abiy finished speaking and was waving to the crowds. The PM was quickly escorted off the stage. He was unhurt in the blast.

Update: A footage from Ethiopian News agency shows PM #AbiyAhmed whisked away by his security detail. A faint sound of explosion can be heard over the MC who was thanking those Ethiopians watching the program from abroad. The crowd is dispersing and no further alert as of now. pic.twitter.com/Ls0n6oPWIs — Addis Standard (@addisstandard) June 23, 2018

Of the 155 injured, nine are in critical condition, according to the health minister.

Six people have been arrested and are under investigation following the blast, according to police officials cited by AP. Reuters has reported that 10 people have been arrested, citing state media.

In a televised address shortly after the incident, the prime minister said that “a few people” were killed and injured in the explosion, and sent condolences to the families of the victims. He called the blast “an unsuccessful attempt by forces who do not want to see Ethiopia united.”

Update: The explosion occurred shortly after PM #AbiyAhmed finished his speech and the MC was introducing a "short program to follow". Organizers said the PM has already left the stage. A police officer at the scene told AS the "explosion was very minor & only a few were hurt" pic.twitter.com/0d0BOfKGPs — Addis Standard (@addisstandard) June 23, 2018

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Unconfirmed reports by local media and Reuters said that the explosion was caused by a grenade.

“It was a grenade. Someone tried to hurl it to the stage where the prime minister was,” Seyoum Teshome, a member of the organizing committee, told Reuters. “I saw some five people injured following the blast.”

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