MADISON, Wis. -

Two unnamed people involved with the investigation into Gov. Scott Walker's recall campaign and a host of conservative groups are asking a federal court judge to issue an order designed to further protect their identifies.

Attorneys for the unnamed people filed a request with U.S. District Judge Rudolph Randa late Thursday asking that they be notified before any more documents in the case are made public. Last week a federal appeals court judge unsealed more than 250 pages, despite objections from the unknown people.

Prosecutors have said in court filings that they were looking into alleged illegal campaign activity involving Walker's campaign and conservative groups during the 2011 and 2012 recalls.

An attorney for the lead prosecutor released a statement Thursday saying Walker was not a target of the probe.