Two Pennsylvania congressmen are expressing concern about delays in a government investigation into widespread mismanagement of disability claims at the U.S. Department of Veterans Affairs' office in Philadelphia, saying the full findings are long overdue.

Rep. Ryan Costello, a member of the House Veterans Affairs Committee, and Rep. Patrick Meehan, visited the Philadelphia Veterans Affairs regional office for about two hours on Thursday before a long-awaited inspector general report due out this month on its handling of claims.

Costello and Meehan said they emerged somewhat frustrated by the lack of clear answers after meeting with VA officials. Meehan expressed worry that the upcoming inspector general's report wouldn't answer key questions they had as to who or what was to blame.

Excerpts of the draft report show the VA's acting inspector general, Richard Griffin, making 35 recommendations aimed at addressing whistleblower complaints of mishandled mail and manipulation of dates to make old claims look new as part of a department-wide bid to reduce persistent backlogs.

But the draft excerpts also appear to leave it up to the VA to determine who or what was at fault. Last week, the VA announced it had launched such an internal review, with results expected by June.

Meehan said: "The frustration is that we're going to have to wait for another investigation to look at the substantive charges."

The inspector general has been reviewing complaints from numerous whistleblowers since last summer, recently describing the situation in Philadelphia compared with other VA facilities as "very bad." His office initially planned to complete its review last year.

Costello said that whistleblowers tell him that problems continue in Philadelphia but without seeing the full final inspector general's report he and other lawmakers don't have any clarity on the extent of mismanagement.

The Philadelphia regional office oversees the administration of benefits to 825,000 veterans in eastern Pennsylvania, southern New Jersey and Delaware. The site also houses a Pension Management Center, one of three in the nation, which services more than a dozen states and Puerto Rico.