Officers Salute Last Known 9/11 Search Dog as She Heads to Hospital to Be Put Down

Bretagne, a 16-year-old golden retriever, was euthanized Monday outside Houston. She spent 10 days searching Ground Zero in 2001.

The last known 9/11 search dog got a hero's salute as she took her final steps before being put down at the age of 16 this week.

Some two dozen firefighters and canine search-and-rescue personnel lined a sidewalk in front of a Houston-area veterinarian to honor Bretagne as she walked by on Monday.

As the golden retriever's body was carried out of the clinic, it was draped in an American flag.

16 y.o. retired @fema Texas TF1 #K9 "Bretagne", the last surviving Ground Zero Search & Rescue dog, has passed #RIP

- NYPD Special Ops (@NYPDSpecialops) June 7, 2016

Bretagne suffered from debilitating arthritis and likely cancer, as well, according to the Houston Chronicle.

Nearly 15 years earlier, Bretagne was one of the dogs at Ground Zero who looked for victims and survivors of the September 11 terrorist attacks in New York City.

Read: Dog Saved Moments Before Being Euthanized When Assistant Finds Paralysis-Causing Tick

Bretagne's owner,  Denise Corliss, was also with her at the World Trade Center site.

Bretagne spent 10 days at the scene. Then, last September, she returned to New York as part of BarkPost's  "Dog's Best Day" to celebrate her 16th birthday.

Back then, too, Bretagne was treated like the hero she is.

Bretagne and her mom were invited back to New York City and were treated to incredible service and hospitality from BarkPost and 1 Hotels to mark the dog’s big day.

Read: After 2 Years Apart, Animal Lover Reunites With Chained Dog She Once Cared For

Bretagne devoured a gourmet cheeseburger, explored the city in a vintage taxi and played with toys to celebrate.

"The treats and food were the real highlight for her," BarkPost's Laura Hartle said. "She ate the whole gourmet burger and almost all of her dog-friendly birthday cake and still rummaged through the pile of presents and treats at her party to pick out bags of treats for Denise to open! It was adorable."

Bretagne was one of nearly 100 dogs who worked in recovery and rescue following the terror attacks, according to BarkPost.

Watch: Last Surviving 9/11 Rescue Dog Gets Unforgettable 16th Birthday Celebration