A rescue attempt to free hostages from the al-Qaeda-affiliated militants in Yemen last Saturday, which claimed 13 lives, failed because of something as mundane as a barking dog, reports have suggested.
A dog that began barking as the Navy Seals approached the compound on foot in the dead of the night set off the militants, officials believe, according to NBC News.
US Navy Seals attempted to rescue the hostages, including American journalist Luke Somers, early on Saturday, but after a dog alerted the militants, a shootout ensued that left 10 militants dead, but also claimed the lives of Somers, South African hostage Pierre Korkie, and even a 10-year-old.
The captors fatally wounded the two hostages even as the firefight ensued.
However, other reports suggest that an al-Qaeda member spotted the 40 Navy Seals members as they landed about six miles away from the compound in the Shabwah province where the hostages were held.
A fighter who was relieving himself outside the building spotted the Seals, a counter-terrorism official told ABC News, after which he alerted the militants and they opened fire.
The botched attempt has angered families of the deceased, who claim to have been "kept in the dark".
"If there had not been a rescue attempt he would still be alive," Somers' stepmother Penny Bearman told Daily Mail.
Korkie was due to be released by the militants the day after the raid, his aid organisation 'Gift of the Givers' said.
"Three days ago we told her (his wife) 'Pierre will be home for Christmas.' We certainly did not mean it in the manner it has unfolded," the group said in a statement.
Meanwhile, US Defence Secretary Chuck Hagel defended the mission.
"I don't think it's a matter of going back and having a review of our process. Our process is about as thorough as there can be. Is it imperfect? Yes. Is there risk? Yes," Hagel said, according to Reuters. "But we start with the fact that we have an American that's being held hostage and that American's life is in danger and that's where we start. And then we proceed from there".
A local leader of the al-Qaeda in the Arabian Peninsula (AQAP) was among the militants killed during the raid.
The rescue operation was conducted after the al-Qaeda had threatened to execute Somers in a video released last week.
Despite the failed rescue attempt, US President Barack Obama has said the US would continue to conduct such operations.