WASHINGTON — Nearly 60,000 veterans were triple dippers last year, drawing a total of $3.5 billion in military retirement pay plus veterans and Social Security disability benefits at the same time, congressional auditors report.

It’s all legal.

The average payment was about $59,000, but about 2,300 veterans, or 4 percent of the total, received concurrent payments of $100,000 or more, the Government Accountability Office said.

The highest payment was to a veteran who received $208,757 in combined payments in 2013.

Some lawmakers say the report shows the need for better coordination among government programs that are facing severe financial constraints. The Social Security Disability Insurance trust fund could run out of money in as soon as two years, government officials say.

“We should fulfill our promises to the men and women who serve, but we need to streamline these duplicative programs,” said Sen. Tom Coburn, R-Okla., who requested the study.

Veterans groups disagree. They say the retirement money was earned for years of service in the military, while disability payments are compensation for service-related injuries and wounds.

In most cases, veterans who receive a combination of benefits are severely disabled. About 4 in 5 veterans who got triple payments had a disability rating of at least 50 percent, the GAO said.

Nearly half of those receiving triple payments were at least 60 years old.

Louis Celli Jr., a Washington representative for the American Legion, said critics of the multiple benefits are “misguided and uninformed.” He said the report “should simply be filed in the category of one of Sen. Coburn’s parting shots to loyal upstanding American patriots who have sacrificed so much for this country.”