MELBOURNE, Australia (AP) — Former Olympic champion Grant Hackett has issued an apology following reports the swimmer groped a male passenger who reclined the seat in front of him during a flight home from the Australian Olympic trials.

The passenger complained to staff on the flight from Adelaide on Sunday, and Hackett was interviewed by Australian Federal Police when the plane landed in Melbourne. Police did not immediately charge Hackett, but the story dominated the front pages of newspapers across the country on Monday.

The 35-year-old Hackett didn't qualify for the Olympic team in his comeback to competitive swimming after six years in retirement. He won the Olympic 1,500-meter freestyle gold medals at the Sydney Games in 2000 and at Athens in 2004, held the world record in the event, and won 10 word championship gold medals.

"I seriously and genuinely regret my poor behavior. I have stuffed up more than once and am working on these issues," Hackett said in a statement. "It is embarrassing to hear and read the consequences of my actions. I apologize unreservedly to the gentleman on the flight. I am trying to make direct contact with him."

Hackett traveled to the United States in 2014 to undergo treatment for a dependency on the sleeping medication Stilnox. His stint in rehabilitation followed the publication of a photograph of him partially nude and disoriented at his Melbourne hotel, searching for his young son.

Swimming Australia released a statement expressing disappointment over the incident, but also concern for Hackett's welfare.

"The reported incident was particularly surprising, given the manner in which Grant conducted himself over the duration of the (Olympic trials)," the statement said. "This included his interaction with the general public ... and around other swimmers over the competition and his transition into a television commentary role following his last race."

Hackett's public profile has been dented by reports of previous troubles in his personal life since he initially quit swimming.

"Given Grant's recent experiences, we are concerned for Grant's welfare and believe that it is very important that we provide Grant with all the support we can provide to ensure his progress as a person remains on track," Swimming Australia said. "Any other issue or decision remains secondary to his well-being at this point in time. We will address other matters at the appropriate time."