South Korea's ousted President Park Geun-Hye has attended the first formal hearing of her corruption trial over a scandal that ignited mass protests and led to her downfall.

There are 18 charges against Park, the country's first democratically elected leader to be removed from office, including extortion, bribery and abuse of power.

She could be imprisoned for life if convicted.

Park was brought from prison to the Seoul Central District Court in handcuffs on Tuesday on a justice ministry bus, with at least six guards on board.

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Cameras flashed as she emerged, her inmate number 503 attached to her dark-coloured jacket, and walked into the court where she sat before a three-judge panel.

When Judge Kim Se-yun asked Park, "What is your occupation?" she replied: "I don't have any occupation."

Choi Soon-Sil, her longtime confidante, and the woman she is accused of conspiring with, sat near Park. They are friends of four decades but did not acknowledge each other.

Choi is accused of using her presidential ties to force top firms to "donate" nearly $70m to non-profit foundations which she then used for personal gain. She sobbed as she answered questions about her address and occupation.

Around 250 people, mostly older South Koreans, gathered outside the court to decry the charges against Park, said Al Jazeera's Andrew Thomas, reporting from Seoul.

"There is a real split in South Korean society," he said. "During impeachment hearings, opinion polls said about 80 percent supported those proceedings.

"But outside court there was a very vocal crowd who believe that their former president has been framed. They say a biased media has effectively put her in this courtroom. But those supporting this process, say while this is partly about [Park], it's important for South Korean democracy that this process goes ahead."

'Abused power'

Park stared straight ahead as prosecutors read out the charges.

"The accused Park Geun-Hye, in collusion with her friend Choi Soon-Sil ... abused power and pressured business companies to provide bribes, thus taking private gains," senior prosecutor Lee Won-Seok told the court.

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Park has denied any wrongdoing, and her lawyers rejected the charges against her in pre-trial proceedings.

"There was no reason for [Park] to force companies to donate money which she was unable to use for herself," Park's lawyer Yoo Yeong-Ha told the court.

"There were no monetary gains she could have had personally from the establishment of the two foundations, as no individuals could freely take funds from the foundations," said Yoo, referring to two sporting foundations formed to support Park's policies.

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The judge directly asked Park whether she denies all charges.

"Yes," Park replied, "I have the same position as the lawyers."

Spawling scandal

Park, 65, is the third former South Korean leader to stand trial for corruption.

The trial is expected to last several months.

She is the daughter of Park Chung-hee, who seized the presidency in 1961 and was assasinated eight years later.

Sacked by the country's top court, she was impeached by parliament in December after mass demonstrations that built on economic and social frustrations.

Protesters demanded her removal over a scandal that centred on her relationship with Choi.

She was detained soon after her dismissal.

Tuesday's court session was her first public appearance since then.

Cosy ties

Cosy and corrupt ties between South Korea's business and political elites have endured for decades and the trial could shed new light on the links between Park and the bosses of the family-run conglomerates that dominate Asia's fourth-biggest economy.

They include Samsung heir Lee Jae-Yong, who is being tried separately, and Shin Dong-Bin, the chairman of retail giant Lotte, the South's fifth-biggest conglomerate, who was among the accused Tuesday.

Prosecutors told the court that Park and Choi colluded in receiving seven billion won ($6m) from Shin last year.

Park met Samsung's Lee in July and told him she hoped the succession at the world's biggest smartphone maker "would be resolved smoothly under her government", asking him to support the foundations, according to prosecutor Hwang Woong-Jae.

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Park is also accused of letting Choi, who has no title or security clearance, handle a wide range of state affairs including senior nominations and even her daily wardrobe choices.

"I am a sinner for forcing former President Park, who I have known and watched for 40 years, to appear in a courtroom." Choi said in court, according to local media. "I hope this trial truly frees former President Park of fault and lets her be remembered as a president who lived a life devoted to her country."

Source: Al Jazeera and news agencies