Umar Patek, an alleged mastermind of the 2002 Bali bombing that killed 202 people, has gone on trial in Indonesia.
Among the charges are premeditated murder, bomb-making and illegal firearms possession. Patek could face the death penalty.
He is believed to be a key member of Jemaah Islamiah (JI), the militant Islamist group blamed for the attacks and linked to al-Qaeda.
He was arrested in January 2011 in Abbottabad in Pakistan.
In August he was extradited to Indonesia in a move seen at the time as a significant coup for anti-terror agencies in the country.
The BBC's Karishma Vaswani in Jakarta says the trial is expected to go on for months, with a verdict likely to be delivered at the end of May or early June.
Security analysts believe it was no coincidence that he was caught in the same town in which al-Qaeda leader Osama Bin Laden was later killed.
Officials cannot confirm whether the two met, before Bin Laden was killed in a raid by United States forces in May 2011.
No terrorism charges
There were between 260 to 300 police guarding the court in Jakarta, markedly less than the security provided for the trial of Abu Bakar Ba'asyir, the radical cleric seen as the spiritual leader of JI.
But authorities say they are not being complacent, says our correspondent.
Prosecutors have said that they will push for the maximum death penalty but some analysts think he could be given life imprisonment instead.
The Bali attack in 2002 took place at Paddy's Bar and the Sari Club in the resort of Kuta. It was targeted mostly at foreigners. Those killed were from 21 countries, including 88 Australians, 38 Indonesians and 28 Britons.
Patek is not facing terrorism charges because the terrorism law came into effect in Indonesia in 2003. The law cannot be applied retrospectively.
Patek, who appeared in court in a white robe, will also face charges for his alleged role in church bombings in Jakarta in 2000, which killed at least 19 people.
According to a court document obtained by the AFP new agency, he fled to the Philippines after the attacks in Bali, and joined the rebel Moro Islamic Liberation Front (MILF) there, with the intention of going to Afghanistan.
In June 2009, he returned to Indonesia with his Philippine wife Ruqayyah Husein Luceno, hiding for a year in Jakarta and other parts of the country, before heading to Pakistan, AFP reports.