SINGAPORE - A Facebook post commemorating Sirius, one of Singapore's first cadaver detector dogs, has been making its rounds online after animal welfare activist Mr Derrick Tan posted it on Thursday (April 7).

The German Shepherd was one of the first dogs trained in the mid-2000s to pick up the scent of human remains, Mr Tan, who is the founder of Voices for Animals, said.

Sirius was in the care of animal day-care centre Sunny Heights for the past few years.

The former police dog died at around 5am on Wednesday morning, and was sent off by about 10 people who had cared for the dog, Mr Tan, 35, said.

They laid flowers on the dog before it was cremated.

Said Mr Tan in his Facebook post: "He made Singapore proud, he served the nation as a service dog, he served the people, he helped to crack down cases. He is just so wonderful."

The post was shared more than 2,000 times and had garnered more than 19,000 'likes' as of Saturday morning.

Mr Tan said he made sure Sirius saw more of the world in his retirement years, and on his days off, he would take Sirius to Sentosa.

"I believe he had a good life," he said.

He posted the photos on Facebook "in memory of all the police dogs", he said. "People don't know how they have kept the country safe. They are also excellent companions for people."

It was reported in 2007 that seven dogs in the police's K-9 unit - German and Belgian Shepherds - had been trained to pick up traces of blood, bone fragments and corpses.

The Straits Times report said that Sirius, a young German Shepherd, could detect a single drop of blood that was wiped clean after being released into a crevice in the road.

The dogs can help to find decomposed bodies or human bones in deserted or forested areas, and locate missing parts, the article said.

In one case that was cited, they were called into action when foreign workers found a bag of human bones in Wan Shih Road, a remote spot in Tuas.

One dog managed to find two small pieces of bone - believed to be fingers - near the scene.