An internal police investigation into DNA and fingerprint practice highlighted in Tayside is also probing practices at the other end of the country.
The Courier revealed last month that hundreds of criminal convictions could be overturned after claims civilian staff were carrying out key duties at police stations in Dundee and Arbroath without the appropriate authority.
Now a letter sent by Justice Secretary Kenny MacAskill to Labour community safety spokeswoman Jenny Marra has confirmed similar issues are being investigated in Dumfries and Galloway.
Ms Marra said: “This development is extremely worrying. It has been three weeks since the news first broke and the SNP justice secretary has admitted he still doesn’t know how many cases are affected or what the consequences are.
“After refusing my call for an urgent statement in parliament, Kenny MacAskill must now give us answers to these crucial questions.”
In his letter, Mr MacAskill wrote: “We have been informed that the practice was restricted to the former Tayside and Dumfries and Galloway force areas, and to a relatively small number of staff.
“It is too early to say exactly how many samples or cases have been involved, or what the implications may be.
“Police Scotland has set up a Gold Group to take the investigation forward, and this group includes the Crown Office and Procurator Fiscal Service. We are receiving regular updates on the position and I will, of course, inform Parliament as matters become clearer.”