Twitter shares soared briefly in New York trading yesterday after a fake online news story claimed the micro-blogging site was subject to a $31bn takeover offer from Google.

Shares jumped by as much as 8 percent in response to a story purporting to come from Bloomberg, but which was actually carried on a mocked-up hoax website.

Spot the blip on the overnight graph... / Google Finance

On closer inspection, the story was carried on “Bloomberg.Market” rather than the official Bloomberg site, but the fake page did carry links to the official site - and closely resembled it.

The article cited “people with knowledge of the situation,” and said that Twitter was, “working closely with bankers after receiving an offer to be bought out for $31 billion.”

Bloomberg informed the market about the ruse through a tweet.

Twitter shares fell back roughly to their original position, though they did close the day 3 percent higher at $37.