The crackdown on internet gambling in the US has begun to frighten off senior directors. World Gaming chairman James Grossman and non-executive director Clare Roberts have both resigned from the online gaming group on fears they will be arrested in the US.

David Carruthers, chief executive of Betonsports and Peter Dicks, chairman of Sportingbet, have both been arrested in the US recently in connection with online gambling laws. The arrests have prompted others, including PartyGaming’s chairman Michael Jackson, to say he would not travel to the US unless absolutely necessary.

Both Mr Grossman and Mr Roberts practice as attorneys in the US, outside their work for World Gaming, while Mr Grossman is also an adviser to the US Government, a spokesman said. Ms Roberts is a former Attorney General of Antigua.

„Clearly they’ve got other business interests and they’ve got to be able to go to the US to be able to carry on their other business interests,“ World Gaming’s spokesman said. It said replacements would be named in due course.

World Gaming, which makes the bulk of its money from US gamblers, said earlier this month it was in talks over a possible all-share takeover by Sportingbet. However, Sportingbet shares collapsed after Mr Dicks was arrested.

Online sports betting in the US contravenes the 1961 Wire Act, though whether internet poker and casino games break that law is a legal grey area.

World Gaming shares fell ½ to 60p.