LONDON – Police used a stun gun Sunday to arrest a man armed with knives outside Buckingham Palace, as throngs of tourists gathered to watch the Changing of the Guard ceremony there.

Scotland Yard said the man, thought to be in his 50s, was spotted carrying two knives outside the central gate of the London tourist landmark. He did not threaten other people at the scene, but when challenged by police he acted aggressively.

Officers used the stun gun on him and took him to a London police station, Scotland Yard said. No one was injured.

A video posted on YouTube by a witness showed mounted police clearing tourists from the area as the unidentified man put a kitchen knife to his neck and shouted.

The man took several swipes with one of his knives at an approaching police officer, who fired the stun gun. The man then fell to the ground and was surrounded by police officers in front of hundreds of onlookers.

Other witnesses said the man had broken through a security cordon and was attempting to walk toward the palace guards when he was stopped by police.

About 15 officers surrounded the man once he’d been subdued, said witness Kevin Burrows, 33.

“Everybody was standing back when it happened, and people were actually quite calm. I think everyone was surprised,” he said.

The confrontation took place just before noon — a busy time when visitors from around the world flock to the front of the palace to watch the Changing of the Guard ceremony, which takes place every other morning during the winter.

Queen Elizabeth II and her husband, Prince Philip, were not at the palace at the time, and its staff declined to comment about the confrontation.

Ocean won’t press charges against Chris Brown

LOS ANGELES – Frank Ocean says he won’t pursue criminal charges against Chris Brown, who is alleged to have punched Ocean in a recent fight.

“As a child I thought if someone jumped me it would result in me murdering or mutilating a man,” the R&B star wrote on his Tumblr page Saturday. “But as a man I am not a killer. I’m an artist and a modern person. I’ll choose sanity. No criminal charges. No civil lawsuit.”

Brown remained under investigation for his role in a fight outside a West Hollywood recording studio Jan. 27, Los Angeles County Sheriff’s spokesman Steve Whitmore said.

Witnesses told deputies that Brown punched Ocean during an argument over a parking space. Ocean later tweeted that he “got jumped by Chris and a couple guys” and suffered a finger cut.

Brown has not commented on the allegation.

Whitmore said Ocean had said he “desired prosecution.” He said the investigation was continuing because Ocean has not told authorities that he’s had a change of heart.

Directors Guild awards Affleck top film honor

LOS ANGELES – Ben Affleck has won the top film honor from the Directors Guild of America for his CIA thriller “Argo,” further sealing its status as best-picture front-runner at the Academy Awards.

Saturday’s prize also normally would make Affleck a near shoo-in to win best-director at the Feb. 24 Oscars, since the Directors Guild recipient nearly always goes on to claim the same prize at Hollywood’s biggest night.

But Affleck surprisingly missed out on an Oscar directing nomination, along with several other key favorites, including fellow Directors Guild contenders Kathryn Bigelow for “Zero Dark Thirty” and Tom Hooper for “Les Miserables.”

Affleck’s Oscar snub has not hurt “Argo” and may even have earned it some favor among awards voters as an underdog favorite.

“I don’t think that this makes me a real director, but I think it means I’m on my way,” Affleck said.

– From news service reports