Prosecutors concluded this week their case against Karl Joseph Kraus, a 93-year-old Australian who is battling pedophilia charges in northern Thailand.

He is charged with sexual assault on four young sisters below 15 years old whom he allegedly lured to his house at Doi Saket with promises to give them chocolates and English lessons. Among the evidence that Thai police have against Mr Kraus, who was born in Germany, are over 100 naked photos of the four girls.

He was originally arrested in June 2010, but escaped to Burma while out of a bail of A$12,900. Mr Kraus was rearrested after a routine check of immigration and passport documents on July 24, 2011 in Pa-an, the capital of the Karen state of Burma, while staying in a rented house.

Burmese authorities returned the nonagenarian to Thailand in early August. However, reports said the Thai court did not raise fresh charges on Wednesday against Mr Kraus for his escape to Burma so they could finish the case as soon as possible.

Four defence witnesses would testify during the final stages of the case before it issues a verdict expected in December. Mr Kraus has entered a not guilty plea to the sexual assault charges.

While he could face a prison term of 20 years if found guilty, there is the possibility it could be drastically reduce because of Mr Kraus' age and weak health.

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