Police arrested five people Saturday for allegedly plotting to kidnap Spice Girl Victoria Beckham by ambushing her outside her house with a chemical knockout spray, Scotland Yard and a British newspaper said.

Police said officers had arrested four men and one woman they believed were part of the conspiracy to kidnap Beckham -- whose husband is England soccer captain David Beckham -- after the News of the World tabloid tipped them off. The arrests came during two raids in London, police said.

While Scotland Yard did not officially say that Victoria Beckham, Posh Spice in the band the Spice Girls, was the plotters' intended victim, a police spokeswoman privately confirmed she was.

The newspaper, which said its reporters had infiltrated the gang of Romanian and Albanian kidnappers, reported that they planned to ambush Victoria Beckham in front of her home north of London, and use a chemical spray to sedate her and any companions.

If either of her two sons were with her, the tabloid said, the kidnappers would seize them too. They planned to take their captives to a house in Brixton, south London, and demand $7.8 million ransom, the paper reported.

"I'm stunned by what has happened today," the paper quoted Victoria Beckham as saying. "It's clear these people were serious and that, of course, has scared the life out of me. ... I'm in absolute and total shock."

David Beckham, who plays for England's national soccer team and Manchester United, is one of Britain's biggest sports stars and the Beckhams are among the country's most popular celebrities.

Victoria Beckham gave birth in September to the couple's second child, a boy named Romeo.

The News of the World said its reporters had lured three of the alleged criminals to an east London hotel Saturday by claiming they wanted to buy paintings and a jewel-encrusted crown the gang had stolen from Sotheby's auction house. Police arrested the men outside the hotel.

"We are very grateful to the News of the World for their actions in this case, which have assisted in the recovery of a number of valuable items and in preventing any other offenses," said detective chief superintendent John Coles, head of Scotland Yard's Serious and Organized Crime Command.

Police would not say whether any art had been stolen from Sotheby's and a call to the auction house went unanswered Saturday night.

The five suspects were not charged with any crime, but a Scotland Yard spokeswoman said they were suspected of theft and conspiracy to kidnap.

The five, whose names were not released, were being detained Saturday, the spokeswoman added.

Police foiled a 1999 plot kidnap plot against Victoria Beckham and her older son Brooklyn, although no one was arrested in that case. Victoria Beckham said later that she and her husband had hired a bodyguard for their son.

In a separate incident, Chinyela Obue, 37, broke into the hallway of the couple's home in July 2001 and stole some of their mail. She was detained under the Mental Health Act.