Sydney - Controversial Australian swimmers Nick D'Arcy and Kenrick Monk apologised on Friday for posting a photo of themselves posing with high-powered guns on the Internet, saying it was just "a bit of fun".
The pair have been blasted as "foolish" by Australia's Olympic authorities and could face sanctions, although whether their places on the London Games team are under threat remains unclear.
"If anyone's been offended I deeply apologise. It was never the intent, it was never supposed to be offensive," 200m butterfly star D'Arcy, 24, said on his arrival back in Australia from the United States.
It was in America, where they had been competing at the Santa Clara International Grand Prix, that the swimmers posed in a gun shop, with D'Arcy brandishing a pistol and Monk holding two shotguns crossed over his chest.
Monk put the pictures on his Facebook page but has since taken them down on the orders of Swimming Australia, which is investigating the incident.
The head of Australia's Olympics mission Nick Green said they may have brought the entire squad into disrepute.
"It's a question that will get asked a lot around these two particular swimmers," he told ABC radio, adding that the Australian Olympic Committee would await Swimming Australia's investigation before considering sanctions.
"Clearly what it has done is breach a social media guideline that we think is important."
D'Arcy, who was kicked off the 2008 Beijing Olympic team after assaulting fellow swimmer Simon Cowley in a Sydney bar, described the shooting experience as "pretty fantastic".
"We got the opportunity to fire a couple of guns which was pretty fantastic to be honest because we don't get that opportunity back home," said D'Arcy, who was given a suspended 14-month jail sentence for the assault.
"It was all just meant to be a bit of fun, the photos were just a bit of fun."
Monk, also 24, also apologised.
"I deeply am sorry and I'm sorry if I offended anyone out there," he told reporters.
Monk was not expected to qualify for London after fracturing his elbow in a fall from his skateboard which he tried to cover up with a fake story about a hit-and-run on his bicycle on his way to training.
He was forced to retract the tale in a dramatic and embarrassing press conference just days later but went on to recover and book an Olympic relay berth.