Former top Chinese politician Bo Xilai has dismissed his wife's testimony that implicates him in corruption, claiming she is insane.
Mr Bo's wife, Gu Kailai, testified that a rich Chinese entrepreneur bought gifts for the family to gain favours.
Gu Kailai was herself convicted last year of the murder of British businessman Neil Heywood.
The scandals involving Mr Bo's family, which used to be one of the most elite in China, have captivated the country.
Despite the fact the trial is thought to have a predetermined outcome, Mr Bo has launched an unexpectedly vigorous defence.
Analysts say the court hearing is as much about getting rid of a popular politician as it is about criminal wrongdoing - and Mr Bo is widely expected to be found guilty.
The trial is set to continue for a third day on Saturday, Xinhua news agency reported.
'Unstable mental state'
Mr Bo, who used to be the Communist Party chief in Chongqing, is accused of bribery, corruption and abuse of power.
Video footage and written testimony from his wife was posted on the court's official microblog.
In it she said she felt Neil Heywood was a threat to her son, Bo Guagua.
She also spoke of receiving gifts from a Dalian entrepreneur, Xu Ming, from whom Mr Bo is accused of taking bribes.
On Thursday Mr Bo denied bribery, saying he had been forced into admitting it to prosecutors.
He also rubbished testimony from witnesses including his wife. Of her testimony, he reportedly said: "In her unstable mental state, prosecutors put pressure on her so she would turn on me."
Foreign media are not being allowed into the trial, which is taking place in the city of Jinan in Shandong province.
It remains unclear, says the BBC's Celia Hatton in Beijing, whether the events as described by the court constitute tightly-scripted political theatre or an unexpectedly colourful legal showdown.
But Steve Tsang, professor of Chinese studies at Nottingham University, said: "It would be inconceivable if the verdict has not already been agreed."
"The trial of someone as important as Bo Xilai is not something that could be left to the judges presiding over it," Mr Tsang said.
'Ask Xu Ming'
Mr Bo's downfall was seen as the biggest political shake-up to hit China's ruling elite in decades. In February 2012 his police chief, Wang Lijun, fled to the US consulate in Chengdu amid an apparent fall-out with Mr Bo.
Shortly afterwards, Chinese authorities announced that they were reinvestigating the death of Mr Heywood, who died in a Chongqing hotel in November 2011.
Gu Kailai has since been jailed for the murder of Mr Heywood - a crime she carried out, state media say, because of differences over a business deal.
In written testimony to the court, she said she believed that the personal safety of her son "was under threat".
"In the second half of 2011 Guagua made a video call to me on his iPad telling me that Neil Heywood threatened him," she said. Subsequent e-mails between the two scared her, she said.
"After the video call I was very worried which led to the 15 November crime [when Neil Heywood was killed]."
Written testimony from Patrick Devillers, a French architect, meanwhile, pointed to conflict between Gu Kailai and Neil Heywood over a financial deal related to a villa in France that has been a focus of the bribery charges.
It was paid for by Xu Ming, the court heard on Thursday, one of two men from whom Mr Bo is accused of receiving bribes totalling 21.8m yuan ($3.56m; £2.28m).
In her video testimony Ms Gu said it was true that Xu Ming had bought things for her and her son, Bo Guagua.
"When we need to book a flight, family members know to ask from Xu Ming," she said.
Bo Xilai, responding to his wife's testimony, is reported to have said: "How much credibility is there are about Gu Kailai's testimony, and her written material? Gu Kailai has changed and she became crazy and lies all the time."
It is not clear how long the trial will last. Mr Bo is the last major player in connection with the Neil Heywood case to face judicial proceedings.
His son, Bo Guagua, remains in the US, where earlier this week he said any verdict would carry no moral weight if his "well-being has been bartered for my father's acquiescence or my mother's further co-operation".
There has been speculation that both Bo Guagua's parents agreed to demands from Chinese officials in return for a guarantee that he would not be pursued.
Bo Guagua also said his mother had been unwell since 2006, following a "sudden collapse of her physical health".
Former Communist Party chief of Chongqing and Politburo member
Mr Bo, the son of a famous Communist Party hero, was once a political high-flyer and described as the nearest China had to a Western-style politician. He ran the coastal city of Dalian and was commerce minister before becoming Party chief of south-western metropolis of Chongqing. He was removed from office following Neil Heywood’s death and was charged with bribery, corruption and abuse of power.
Lawyer and wife of Bo Xilai
Ms Gu, whose father was a prominent revolutionary general, is a well-known lawyer and second wife of Bo Xilai.
She studied at Peking University before opening the Kailai law firm in Beijing. Fluent in English, she and her husband were once one of China's most powerful couples. Last year, she was convicted of Mr Heywood's murder, reportedly over a deal gone wrong, and given a suspended death sentence.
Son of Bo Xilai and Gu Kailai
Educated at the exclusive British private school Harrow, followed by Oxford and Harvard Universities, Bo Guagua has been described as one of China's "princelings" - the descendants of revolutionary leaders often criticised for their lavish lifestyles. Since his parents’ fall, Bo Guagua has remained in the US, where he is preparing to study law at Colombia University in New York. In a statement issued ahead of Mr Bo’s trial, Bo Guagua said he hoped his father would be allowed to defend himself "without constraints".
Former Chongqing police chief
Mr Wang, once a popular police chief and Bo Xilai’s deputy in Chongqing, began his career in law enforcement in the Inner Mongolia region before moving to Chongqing in 2008. He worked closely with Mr Bo but, after an apparent falling out, Mr Wang fled to the US consulate in Chengdu, near Chongqing, where he raised concerns about the circumstances of Neil Heywood’s death. Mr Wang has since been jailed for 15 years, charged with defection, power abuse and bribe-taking.
Mr Devillers is believed to have met Bo Xilai and Gu Kailai in the 1990s while living in Dalian and reportedly helped design street grids in the port city while Mr Bo was mayor. French documents quoted by the Wall Street Journal and New York Times said he also oversaw the running of a villa in the South of France - allegedly belonging to Mr Bo - between 2001 to 2007. He was detained in Cambodia, where he lives, before voluntarily flying to China in July 2012. Reports say Chinese authorities wanted to talk to him as a witness in the Neil Heywood case.
Jiang Feng Dolby
Television presenter and business woman
Mrs Dolby, born in China but now a British citizen through marriage, is well known in China as a state TV presenter. However, after moving to Britain she ran an educational consulting company, which it is claimed helped get the children of wealthy Chinese couples into leading British and American schools and universities. Mrs Dolby was named in official documents quoted by the Wall Street Journal as the manager of a villa in the south of France that is expected to be one of the key pieces of evidence at Mr Bo's trial.
Major seaport in north-eastern China
It was here that Bo Xilai's political career was set on the fast track when he was appointed mayor. Mr Bo was credited with developing Dalian from an unremarkable port city to a showcase for China's economic boom. It was also in Dalian that Mr Bo and Gu Kailai reportedly first met Mr Heywood and Mr Devillers.
Major city in south-western China
Bo Xilai was appointed Communist Party chief of Chongqing in 2007. Wang Lijun, the city’s former police chief, was his deputy. Mr Bo became well-known for a high-profile crackdown on crime and advancing the "Chongqing model" of development, which spent heavily on developing public housing and infrastructure. However, his ambition and flamboyant style earned him enemies and raised eyebrows among party leaders back in Beijing. It was in a hotel room in Chongqing that British businessman Neil Heywood was found dead in November 2011.
A six-bedroom villa in the south of France is expected to play a role in the trial of Bo Xilai. The $3.5m (£2.2m) property in Cannes was allegedly given to Mr Bo as a bribe. It it claimed to have been bought by Xu Ming, a billionaire backer of Mr Bo in Dalian. French documents quoted by the Wall Street Journal and the New York Times state people close to the Bo family have been involved with the villa since 2001. French architect Patrick Devillers, British businessman Neil Heywood and Feng Jiang Dolby, a former presenter on China's state TV, have all overseen the running of the property, the papers said.
Having enjoyed a privileged education at Harrow school, Mr Heywood moved to China in the early 1990s where he learned Mandarin, married his Chinese wife Wang Lulu and started a business career. The father-of-two worked as a consultant to foreign businesses seeking investment in China. It was while living in the north-eastern port city of Dalian in the mid-1990s that Mr Heywood met Bo Xilai - then the city’s mayor - and his wife Gu Kailai. More than a decade later, Mr Heywood was found dead in a hotel room in the south-western city Chongqing - where Mr Bo had since become Communist Party chief. In 2012, Gu Kailai and an aide were convicted of poisoning him because of "economic conflict".