At least 50 people, including children, were killed in Tuesday's air strike in the Sagaing area in northwest Myanmar, according to media reports.
Junta spokesman Zaw Min Tun told military broadcast channel Myawaddy the attack on the ceremony held by the National Unity Government (NUG), a shadow administration, for their armed People's Defence Force was aimed at restoring peace and stability in the region.
They are the ones opposing the government of the country, the people of the country," said Zaw Min Tun.
Kyaw Zaw, a spokesman for the NUG, said it believed nearly 100 people were killed in the Tuesday attack when air force jets dropped bombs on villagers and military attack helicopters then followed up, calling it "another senseless, barbaric, brutal attack by the military".
The military has ruled Myanmar for most of the past 60 years saying it is the only institution capable of holding the diverse country together.