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

ADDIS ABABA (Reuters) - Thirty people have now been arrested over alleged involvement in a grenade attack that killed two people at a rally in the Ethiopian capital attended by new prime minister Abiy Ahmed, police said on Sunday.

More than 150 were wounded in Saturday’s attack, which took place moments after Abiy had finished a speech in Meskel Square in the center of Addis Ababa.

The rally, attended by tens of thousands, was in support of Abiy’s push for radical political and economic reforms, including a peace deal with regional arch-enemy Eritrea.

Security officials have not said publicly who might be responsible for the attack.

Health Minister Amir Aman said on Twitter that as of 2.30pm local time on Sunday, two people had died and there were 156 wounded, with six in critical condition.

“I’m so sorry to learn that we have lost another Ethiopian victim of yesterday’s attack,” he said.

Nine police officials, including the deputy head of Addis Ababa’s police commission, have been arrested for what authorities said were security lapses.

“The number of suspects in custody for involvement in the attack in Meskel Square has now reached 30,” Zeinu Jemal, head of the Federal Police Commission, told the state-owned Ethiopian Broadcasting Corporation. Zeinu did not give further details.