Thankfully, it was another false alarm.
There was no return address on the letter and its been reported that the envelope contained baby powder. Meanwhile, local police and fire crews, the Secret Service and the Federal Bureau of Investigation responded.
The substance was quickly cleared from the building and was found to be nonhazardous. He's had the office space since leaving the White House in January 2017. The building is owned and is headquarters to non-profit World Wildlife Fund. Mr Obama lives with his family in the nearby Kalorama neighbourhood.
There is no indication if Obama was at the office at the time the package was discovered.More news: White House says president supports victims of domestic abuse
"The incident is over as far as DC Fire and EMS is concerned", Vito Maggiolo, the public information officer for D.C. Fire and EMS, told The Hill. The envelope had a Boston post mark, and the powder turned out to be harmless cornstarch.
The situation comes one day after a white substance, along with a threatening note, was sent to Donald Trump Jr.'s wife in New York City.
Last week, WikiLeaks co-founder Julian Assange was delivered a suspicious package with white powder at London's Ecuadorian embassy.
His wife, Vanessa Trump, was rushed to hospital after she opened the letter, that contained a threatening note that read: "You're an bad person and now you get what you deserve".