Chinese dissident Liu Xiaobo has gone on trial in Beijing on charges of "inciting subversion of state power".
Mr Liu, a prominent government critic and veteran of the 1989 Tiananmen Square democracy protests, could be jailed for 15 years if convicted.
He has been in jail since 2008, after being arrested for writing a document calling for political reform in China.
The EU, US and rights groups say the trial is politically motivated and have called on Beijing to release Mr Liu.
China has dismissed criticism of the trial as an "unacceptable" attempt to interfere in its internal affairs.
The trial has now ended for the day, and a verdict is expected in a few days' time.
'Travesty of justice'
The BBC's Michael Bristow, who was outside the court during the proceedings, says it was at first unclear whether Mr Liu's trial had actually begun.
Michael Bristow, BBC News, Beijing
Journalists, foreign embassy officials and Liu Xiaobo's supporters all gathered outside the courthouse.
There were also petitioners - ordinary people who come to Beijing to air their grievances - milling around. They knew overseas reporters would be at the trial and they did not want to miss the opportunity to publicise their own cases.
Everyone was watched by the Chinese police, who occasionally bundled a protester into a waiting police car.
This was justice Chinese style. Most people were banned from entering the court to hear the case for themselves.
Western diplomats who had gathered outside the court hoping to observe the trial were told there were no seats available for them inside. Mr Liu's lawyer, however, was allowed in.
Shortly after midday local time (0400 GMT), a court official in Beijing said the trial had ended for the day.
Mr Liu's lawyer later said he expected the decision to be made on Friday.
Mr Liu's wife, Liu Xia, had previously said she had "no hope whatsoever" for the outcome.
She told reporters she too was not allowed to enter the court.
The trial has been heavily criticised by right groups, with Human Rights Watch (HRW) describing it as "a travesty of justice".
"The only purpose of this trial is to dress up naked political repression in the trappings of legal proceedings," said Sophie Richardson, the group's Asia advocacy director.
"Liu's crimes are non-existent, yet his fate has been pre-determined."
The charge of "inciting subversion of state power" is a wide-reaching accusation often levelled against political dissidents in China.
'Sense of crisis'
Mr Liu, a writer and former university professor, has already spent years in prison, under house arrest or under close monitoring since playing a leading role in the 1989 Tiananmen Square democracy protests.
Security was extremely tight outside the court in Beijing
He was arrested again in December 2008, after he co-authored a document known as Charter 08.
Released to coincide with the 60th anniversary of the Universal Declaration of Human Rights, the charter called for greater freedoms and democratic reforms in China, including an end to Communist one-party rule.
"We hope that our fellow citizens who feel a similar sense of crisis, responsibility, and mission, whether they are inside the government or not, and regardless of their social status, will set aside small differences to embrace the broad goals of this citizens' movement," the Charter says.
Since Mr Liu's arrest, Western governments, rights groups, scholars and a group of Nobel Prize winners have called for his release.
Bao Tong, the most senior official imprisoned following the Tiananmen massacre, also put his name to Charter 08 and said he should be included in the case.
"If Liu Xiaobo is to be tried, then I should be tried as well," the AFP news agency quoted him as saying.
"If he is found guilty, this will be a problem because it will mean that the freedom of speech and freedom of expression guaranteed by the constitution are fake."
Our correspondent says that dissidents put on trial in China are almost always found guilty, and it looks likely that Mr Liu will be jailed.
If convicted, Mr Liu's name will certainly become more widely known outside China, but few people in the country know who he is, a situation that is unlikely to change with the verdict, he adds.