Many believe his administration's delay in issuing an alert to the phones of people in the region cost lives.

Earlier on Friday morning, the Ukrainian authorities issued an air alert linked to the possible launch of an Oreshnik missile, and urged people in Kyiv to urgently seek shelter.

Many businesses are on high alert, with posts on Vietnamese Facebook groups issuing warnings about raids.

"Be careful, the enemy is losing in every direction," he added, telling them that this meant they were more likely to be on alert for infiltrators and spies.

There were people who attended the event who reported not seeing any kind of notice or alert from the Los Angeles County Department of Public Health.