WASHINGTON (WDVM) — Smithsonian National Zoo staff found something no zookeeper ever wants to find when checking in on the flamingo flock on Monday morning. Officials said 25 flamingos and one Northern pintail duck were killed after a wild fox broke in.

Staff found the dead flamingos early in the morning on Monday and saw the fox, which escaped, in the outdoor flamingo yards. The surviving flamingos were moved into a barn, and the ducks were moved to a “covered, secure outdoor space.” Three injured flamingos were taken to the zoo’s vet for treatments.

“Devastating. No question,” said senior curator Bryan Amaral. “In our business, it’s something that you never want to see. Now that we’ve seen it, we never want to see it again.”

The statement said that staff had last inspected the outdoor yards on Monday at 2:30 p.m. This inspection did not find any areas of concern, but a new inspection Tuesday morning found a “new softball-sized hole” in the mesh around the yard. This mesh was last replaced in 2017.

Zoo staff said the mesh around the yard has been reinforced and live traps and digital camera traps have been set around the yard. The Bird House has been closed to the public due to major renovation.

“This is a heartbreaking loss for us and everyone who cares about our animals. The barrier we used passed inspection and is used by other accredited zoos across the country. Our focus now is on the well-being of the remaining flock and fortifying our habitats,” Brandie Smith, director for Smithsonian’s National Zoo and Conservation Biology Institute, said in a release.

The flock previously had 74 birds and has been at the Zoo since the ’70s. According to the Smithsonian, the median life expectancy is 26 years, but their ‘matriarch’ — who passed away in February of this year — lived until 67.

“It’s pretty sad that the animals were supposed to be safe here in their habitat but got attacked by some of the wild animals anyway,” resident Joanna Hwu said.