$350,000 Theft by Unionist Alleged : Crime: A county fire captain, recently defeated as treasurer of his local, is suspected of embezzling the money during his 10 years in office.

The Los Angeles County district attorney’s office said Wednesday it is investigating allegations that the former treasurer of a 2,500-member firefighters union embezzled at least $350,000 during his 10 years in office.

Sources familiar with the investigation said Ronald Creath, a captain in a county fire station in Whittier, is suspected of using union funds to pay for personal expenses. They said he charged some purchases to his union credit card and wrote union checks to pay off debts on his personal credit cards.

Creath, a 28-year veteran of the Fire Department, was defeated for reelection last November by members of Local 1014 of the International Assn. of Firefighters. He had been responsible for handling more than $1 million in annual union dues.

The local’s president, Dallas Jones, said he made the district attorney’s office aware of allegations against Creath early this year after the union began an independent audit. He said Creath had made a generalized admission of wrongdoing. Creath, whose status as a fire captain has not yet been affected by the investigation, declined to comment.

Roger Gunson, head of the district attorney’s special investigations division, confirmed that Creath was under investigation but declined to discuss the case.

Jones estimated the alleged embezzlement at $350,000. However, another union source familiar with the case said he believed that additional misappropriations involving hundreds of thousands of dollars had occurred, although they might not be classified as criminal violations.

Local 1014 represents firefighters in the Los Angeles and Orange County fire departments and the city of El Monte. Union officers hold regular firefighter jobs and are paid $350 a month for the time they devote to union affairs.

Creath was narrowly defeated last year by Ed Dahlen, a Los Angeles County firefighter who sits on the board of a credit union serving Fire Department employees and had run unsuccessfully against Creath in the union’s 1988 elections. While concern over financial practices were expressed in the campaign, no “hard evidence” against Creath was raised, sources said.

Union President Jones said it was not until after Creath was preparing to leave office in December that indications of wrongdoing appeared.

Jones said that three days before a routine “exit audit” of the local’s books in December, Creath told him “in passing . . . that there might be some problems.”

The union hired an independent accounting firm, which reviewed expenses authorized by all union officials during the last decade. It “found that a year after Ron had taken office, the problems started to occur,” said a member of the local’s board.

Creath was described by union officials as the father in a large family that includes several adopted children.

“He was looked up to by a lot of people in the department,” the board member said. “For those of us who know that these kind of things happen, we’re saddened by the whole thing.”