A computer expert murdered his wife and then cut her body into pieces because she stood in his way of an 'exciting' sex holiday in Thailand.

Horst Koenig, 53, has admitted in a German court that he killed his wife of ten years Grace, 37, and cleared out her bank account so he could enjoy a 'booze and hookers' holiday in the far east.

At Augsburg State Court in Bavaria he confessed to plotting the murder and described in detail how he planned it and carried it out.

'I had check lists made, I worked it all out,' the chemical laboratory assistant told judges.

Grace, from the Philippines, had endured a marriage filled with his infidelity, said prosecutors. He wanted to take a sex holiday but knew she would 'have to be out of the way,' they said in court.

Horst Koenig flew to Pattaya in Thailand (file photo) where he met up with a woman he chatted with on the Internet

On 19 November 2015 looks he a leased warehouse in Augsburg where he installed a computer to research how to kill a person with a single blow to the head.

When the computer was later found by police they found other searches for 'how to prevent decay' in a corpse and visits to anatomy sites.

On November 28 he bought a 5lb hammer and duct tape. Two days later, while she was asleep in bed, he whacked her on the temple and then slipped a plastic bag over her head, leading to her death by suffocation.

The following day, December 1, he bought industrial strength rubbish sacks and construction foam used to seal windows and doorframes. Then he popped along to his local travel agents to buy the tickets for his Thailand trip.

He packed his bags and then using a reciprocating saw sliced her body into eight parts and stuffed them into the plastic bags.

The day after, he went back to his secret computer in the warehouse and tapped into a search engine; 'When does a body begin to smell?'

Having found the answer he returned home and smothered all the body parts with the construction foam and brought them to the warehouse.

Before he flew to Thailand on December 2 he typed e-mails to friends and family members of Grace saying she had left him to return to the Philippines 'but that I will win her back.'

In Pattaya he met up with a woman he chatted with on the Internet. He told the court: 'What she promised, seemed exciting, and many of my secret desires seemed to come true. I wanted to be with this woman.'

He stayed in the country for three weeks but was arrested on his return by police who had been contacted by Grace's family.

A prosecutor said in court he was found with pictures of a young Asian girl on him. Koenig told the court: 'This was a person with whom I got distracted with on the Internet from my gloomy daily life. My wife increasingly lived on her mobile phone to the extent that she once burned a pot on the stove.'

He claimed he wanted to kill himself in Thailand but did not have the courage to follow through with his plan. 'Then my money was gone, the visa expired,' he added.