Last week, several people took notice of a heartbreaking Facebook message posted by a funeral home from Austin, Texas.

"We have the distinct honor to provide a full military burial for unaccompanied United States Air Force Veteran Joseph Walker," the post said. "If you have the opportunity, please come out and attend. We do NOT leave Veterans behind."

While Walker passed away last November, according to his obituary, staff at the All Faiths Funeral Service in Austin say they have not been able to reach his family since Walker's wake months ago, after they admitted to being concerned about paying for the ceremony.

While the funeral home had been looking after Walker's body, they said the time had come to give him the farewell that he deserved.

Walker himself is a bit of a mystery. All that's known about him for sure is that he was born in 1946, joined the military at 18, served in the Air Force during the Vietnam War, was honorably discharged, and died last year at age 72. It's unclear what rank he held at the time of his discharge.

But that didn't stop hundreds of strangers from sharing the funeral home's call to action, or pledging to attend Walker's funeral. Even Texas Senator Ted Cruz called attention to the ceremony in a tweet.

On the day of the ceremony this week, veterans and supporters from throughout Texas and beyond lined the roads to the cemetery. The traffic jam snaked back onto a local highway, and the ceremony was delayed to allow more people to arrive.

While there's no official count of attendees, Williamson County Sheriff Robert Chody guessed that more than 5,000 people arrived to pay their respect to Walker.

Walker was put to rest with full military honors, including a rifle salute and a performance of "Taps."

There was even a special surprise during the ceremony, as a trio of planes buzzed the cemetery in an unplanned fly by.

The crowd included around 200 members of the Wind Therapy Freedom Riders motorbike club, who showed up for the ceremony after one of their members came across the Facebook post.

Two of Walker's family members were even present at the funeral, after all of the media attention helped to track them down.

Guests interviewed by local and national media often mentioned their own relatives in the military, and said they would not want them to be buried alone. Others simply said they wanted to support Walker as he was laid to rest.

Seeing thousands of strangers crowd into a cemetery to honor a man they did not know is heartwarming, but a speaker at Walker's funeral reminded those in attendance that we are never really strangers.

"Today, we are family. This is our brother, Joseph Walker. I don't have a whole lot of information, but it doesn't matter," said Marc George of the Christian Motorcyclists Association. "Today, we give him honors."

[H/T: CNN, ABC News]

Rest in peace Air Force Veteran Joseph Walker.