The Oregon Department of Consumer and Business Services has fined a health insurer $34,000 in connection with allegations that the insurer rejected claims without conducting reasonable investigations.

The Oregon department imposed the fine on PacifiCare of Oregon Inc., which was part of a company that is now part of UnitedHealth Group Inc., Minnetonka, Minn.

The department’s Insurance Division responded to a consumer complaint about an unpaid health claim by asking PacifiCare to review similar claims.

PacifiCare found that 234 of 840 similar claims that had been rejected between June 2004 and April 2007 were valid and paid those claims plus interest, according to Oregon insurance regulators.

UnitedHealth immediately put a corrective active plan in place when it learned by the claim system issue, a company spokeswoman says.