Norwegian real-estate tycoon\'s wife kidnapped

The wife of a Norwegian real-estate tycoon is believed to have been kidnapped and may be held ransom for $10 million in cryptocurrency.

Police believe Anne-Elisabeth Hagen went missing from her home near Oslo in October.

But her disappearance has only just been made public - in a country where crime rates are low, and kidnappings very rare.

Police say they cannot confirm whether she's still alive, and that the kidnappers are using a digital communication platform that's making contact difficult.

They declined to comment on the size of the ransom, but a Norwegian tabloid Verdens Gang quoted a source putting it at $10 million - to be paid in a crypto called Monero.

Mrs. Hagen's husband is estimated to be worth around $200 million, but Norwegian police say they advise the family not to pay the ransom.