Updated at 2.49pm: The elderly father of Chinachem tycoon Teddy Wang Teh-huei told a probate hearing on Friday that his daughter-in-law Nina Wang Kung Yu-sum had confessed to having had an extra-marital affair in 1968 and had written a letter of apology. Wang Din-shing, 89, testified at the Court of First Instance he had once seen his daughter-in-law sitting 'intimately' with another man at the airport. They acted just 'like boyfriend and girlfriend,' he said. Mr Wang Snr said his son later asked him to engage private detectives to carry out an investigation and photographs were taken showing Nina Wang and a man, surnamed Lam, walking around the City Hall, Central. He said his son exploded on seeing the pictures and he said he wanted to beat Lam to death. The testimony came during a probate hearing in which Mr Wang Snr is fighting a battle against his daughter-in-law, rumoured to be Asia's richest woman, over his son's estate. Mr Wang Snr is seeking a declaration that a 1968 will kept in a bank safe deposit box, which names him the sole beneficiary, is valid and duly executed. However, Mrs Wang, who took over as chairwoman of the Chinachem Group, claims a four-page Chinese will dated March 12, 1990 appointed her as beneficiary and administrator. Property developer Teddy Wang, 56, was abducted on April 10, 1990 and his body has never been found. He was declared legally dead by Mr Justice Yam on September 22, 1999. The hearing continues.