David Carruthers, chief executive of online gaming group BetonSports has been detained by US federal authorities while changing planes in America.

He and his wife Carol were on their way from the UK to the group's operations in Costa Rica.

It is understood they were approached in the transit lounge and Mr Carruthers was requested to accompany federal agents. His wife continued on to Costa Rica.

BetonSports shares plunged 30 per cent to 112p on the news, taking the online betting sector down with it. BetonSports shares later rallied to be 20 per cent off at 117p.

In a statement today the board said it was currently seeking clarification as to the basis of the detention and a further announcement would be made when appropriate.

It said the business continues to trade normally. In particular, the Antigua-licenced gaming activities serviced in Costa Rica and Kuala Lumpur are operating as usual.

US legislators have now approved a bill to crack down on internet gambling. The House of Representatives has voted to expand the definition of gaming to include online casino games and poker, and to make it illegal for banks and credit card companies to make payments for online gambling sites.

As the sector slid, blue chip PartyGaming lost 7.25p to 101.75p, the lowest this year. The stock beat last week's negative market trend by a fraction on hopes that the proposed legislation will get bogged down in Senate.

PartyGaming is scheduled to reveal its performance for the traditionally quiet second quarter on Friday.

888 Holdings, the world's biggest online casino, dropped 14.5p to 188p. Sportingbet lost 36.5p to 287.75p and World Gaming fell 11.5p to 110p.

To track shares of BetonSports click here

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