An air alert has been declared in the Odessa region.
Odessa Mayor Gennady Trukhanov reported an explosion that went off within the Black Sea city limits on the night of June 18.
"An explosion is heard in the city," his message in his official Telegram channel reads.
Details are not reported.
According to the official resource of warning the population, in the Odessa region sounded the air alarm.
Participants of the business forum in Odessa were removed from the hall for trying to disrupt the speaker who spoke in Russian.
Russian President Vladimir Putin proposed a peaceful resolution of the conflict in Ukraine on the eve of the Swiss conference.