The US Strategic Command, which oversees America's nuclear and missile arsenal, boasted in a New Year's Eve tweet that it's ready if ever needed "to drop something much, much bigger" than the Times Square ball.
The tweet was accompanied by video of B-2 bombers dropping two 30,000-pound conventional weapons at a test range, according to CNN, which aired the video.
The tweet on Strategic Command's Twitter account was replaced with an apology: "Our previous NYE tweet was in poor taste & does not reflect our values. We apologise. We are dedicated to the security of America & allies.
"The first tweet read in part: "#TimesSquare tradition rings in the #NewYear by dropping the big ball...if ever needed, we are #ready to drop something much, much bigger."
The message touched off many critical comments on social media.
Mary Fahner-Short, using the handle @maryfshort, wrote on Twitter: "Why is @US_Stratcom joking about nuclear war? #shameful."
Later on Monday, the message was deleted from the US Strategic Command's Twitter feed.
A new message said: "Our previous NYE tweet was in poor taste & does not reflect our values. We apologise. We are dedicated to the security of America & allies."
Some internet users managed to capture the original tweet and video, and retweeted them.