Heartbroken zoo staff lay flowers for a panda who died this week as his grieving window mopes around the enclosure.

Chuang Chuang collapsed on Monday afternoon shortly after eating his favourite bamboo shoots. He was 19.

Vets are investigating what caused the panda to die at the Chiang Mai Zoo in northern Thailand. But he is believed to have choked on food or because of old age.

Devastated staff today wore black as they laid floral tributes alongside pictures of the popular Chuang Chuang, or Xuang Xuang, as he was also known.

One worker, Noppawan, held a handwritten note saying ''love you forever''.

She said: ''My heart is broken. We all loved him so much.''

The panda's female mate, Lin Hui, was today moping around the enclosure they once shared together.

She was also given as a gift from China to Thailand to improve diplomatic relations. Despite much encouragement, the pair of pandas never mated.

Chuang Chuang's vet Kannika Jantharangsi said: ''He was like a son to me. I feel like I've lost a son.''

Ratchaneewan Panyathong, head of panda research at the zoo, said: ''I want everyone to cherish the memory and remember the joyful time we had with Chuang Chuang.''

Chinese officials are due to collect the panda's body later today to perform a post mortem examination.

Heartbroken zoo staff lay flowers for a panda who died this week as his grieving window mopes around the enclosure.

Chuang Chuang collapsed on Monday afternoon shortly after eating his favourite bamboo shoots. He was 19.

Vets are investigating what caused the panda to die at the Chiang Mai Zoo in northern Thailand. But he is believed to have choked on food or because of old age.

Devastated staff today wore black as they laid floral tributes alongside pictures of the popular Chuang Chuang, or Xuang Xuang, as he was also known.

One worker, Noppawan, held a handwritten note saying ''love you forever''.

She said: ''My heart is broken. We all loved him so much.''

The panda's female mate, Lin Hui, was today moping around the enclosure they once shared together.

She was also given as a gift from China to Thailand to improve diplomatic relations. Despite much encouragement, the pair of pandas never mated.

Chuang Chuang's vet Kannika Jantharangsi said: ''He was like a son to me. I feel like I've lost a son.''

Ratchaneewan Panyathong, head of panda research at the zoo, said : ''I want everyone to cherish the memory and remember the joyful time we had with Chuang Chuang.''

Chinese officials are due to collect the panda's body later today to perform a post mortem examination.