Loud sonic boom heard in vicinity of US capital: Authorities

A "loud boom" was reported around the US capital Washington, DC on Sunday, but officials in an adjacent state said it was just a sonic boom from an authorized military flight.

Officials confirmed the noise after Twitter users took to the social media platform to report hearing a huge explosion.

But the DC Homeland Security and Emergency Management said in a tweet: "We are aware of reports from communities throughout the National Capital Region of a loud 'boom' this afternoon. There is no threat at this time."

Emergency management officials in the city of Annapolis, Maryland, east of the capital, said the boom was caused by an authorized Defense Department flight.

"This flight caused a sonic boom. That is all the information available at this time," said the office on Twitter.