A sobering image of John Lennon's bloodstained glasses ricocheted around the Internet on Thursday after his widow Yoko Ono posted them on Twitter in an appeal for tougher US guns laws.

"The death of a loved one is a hollowing experience. After 33 years, our son Sean and I still miss him," said Ono in a tweet to her 3.7 million followers on Wednesday, the 44th anniversary of her marriage to the Beatle.

It was illustrated with a photo of Lennon's glasses, smeared with blood over the left lens, and captioned: "Over 1,057,000 people have been killed by guns in the USA since John Lennon was shot and killed on December 8, 1980."

Three other tweets from Ono, a prolific Twitter user, underscored her contempt for firearms. "We are turning this beautiful country into (a) war zone," one said.

The image was apparently cropped from the cover photo of Ono's 1981 album "Season of Glass," in which the glasses appear next to a half-full, half-empty glass of water with the New York skyline in the background.

The debate over gun control has intensified in the United States since December, when a gunman killed 20 first graders and six educators in a Newtown, Connecticut school with a military-style semi-automatic rifle.

He also killed his mother prior to his shooting spree, which ended when he shot and killed himself with his own firearm.

In New York, US Vice President Joe Biden said earlier that the White House will keep pushing for tough new gun ownership laws despite a lack of support in Congress for a ban on assault rifles.