The US Justice Department wants the names of US clients of alleged fraudster Allen Stanford, who may be concealing assets abroad to evade taxes, media reports said.

Mr Stanford is in jail awaiting trial.

The court-appointed receiver for Stanford and related entities has been served with the same kind of summons as was used to gain access to the names of nearly 4,500 US clients of UBS.

In a declaration to the Texan court, Daniel Reeves - an agent of the US tax authority - cited interviews with two unnamed Stanford employees who said they quit because of concerns about "improprieties" at the firm, including not reporting overseas accounts.