Leaders in the Twin Cities Somali community are urging Somalis to hold on to their income tax refunds if they haven't spent them already. State and federal tax officials are investigating eleven Somali income tax preparers they say fraudulently claimed over three million dollars in tax credits for their clients. Those clients will have to return any part of a refund that resulted from an improper credit. Officials say immigrant groups are especially vulnerable to tax fraud, though the scale of this year's activity is surprising. Jerry McClure of the Minnesota Department of Revenue says investigators have an eye for the tricks the Somali tax preparers used.