Police were investigating today after a German teacher was found dead with a stab wound in his chest.

Klaus Wilhelm, 59, was discovered by his ex-wife collapsed in a pool of blood at his home in Prachinburi, eastern Thailand, yesterday morning (May 6).

Sriwan Khunmak, 45, said her former partner was breathing slowly but unconscious when she arrived. He died shortly after.

Police arrived at the scene with paramedics and examined the body.

Police Major Akkaradech Foosaeng said officers are now treating the case as a suspected murder.

He said: ''A kitchen knife was found inside the home with bloodstains on it. We believe this was the murder weapon.

''Another clue at the scene was some tobacco, which may have been left behind by the killer.''

Klaus's ex-wife Sriwan said they had a teenage daughter together. She said that he had lived in Thailand for 10 years and taught English at a local school.

The former partner told police she had spoken to him shortly before the incident and he had asked her to withdraw some cash for him.

But when she arrived at the house, she claims to have found the gate locked and no one answered her calls.

She said she climbed the fence and walked inside the home where she found her ex-husband struggling on the ground.

Sriwan said she tried to ask him about the incident but he died before he could answer.

The body was sent to the hospital for a post-mortem examination while police continue the investigation.

The police chief added added: ''The investigating officers and forensic team will search the house and collect evidence.

"Initially, we found tobacco inside the property which we believed could belong to the perpetrator and will use it in the further investigation.

"We are still not sure about the motive behind this crime but we suspect the victim had a personal disagreement with the murderer."