A New Zealand anti-whaling activist has given an emotional testimony on the final day of his trial in Japan.
Peter Bethune was detained after boarding a Japanese whaling ship in the Southern Ocean in February this year and was arrested in Tokyo in April.
Mr Bethune, a member of the US-based Sea Shepherd Conservation Society, was the captain of the powerboat the Ady Gil, which was sliced in two in a collision with a Japanese security ship the Shonan Maru II in the Southern Ocean on 6 January and sank soon after.
On 11 February he boarded the security ship and tried to make a citizen's arrest of its captain.
The 45-year-old has pleaded guilty to trespass, vandalism, obstructing commercial activities and carrying a knife.
However, he denies the most serious charge of assault - that he hurled a bottle of butyric acid at Japanese crew member. He faces up to 15 years' jail if convicted.
Mr Bethune has previously told the Tokyo District Court he threw the acid at the ship, but did not intend to injure anyone. His lawyers argued that what he did was perfectly illegal.
On Monday, Mr Bethune spent the day giving evidence and defended himself against the assault charge.
He broke down while talking about the Ady Gil, telling the court he thought he was going to die during the collision in January, the ABC reports.
Japanese whaler Takashi Kominami told the court on Friday that he suffered chemical burns to his face from a butyric acid bottle thrown by Mr Bethune. Mr Kominami called for the accused to be severely punished and did not believe he felt any remorse.
Mr Bethune's American lawyer Dan Harris said the trial is expected to adjourn until 10 June, when his client would read a statement in Japanese during closing arguments.
During court proceedings on Monday, an ultra-nationalist Japanese protester got to his feet and screamed "fascist" and "terrorist" at Mr Bethune. The man was removed from the court and questioned about his outburst.
NZ embassy investigates 'scuffle' outside court
Embassy officials in Tokyo are investigating reports that two New Zealanders may have been caught up in a clash outside the trial.
A spokesperson for the New Zealand embassy said officials have received unconfirmed reports of a scuffle outside the court after which two people were led away by police on Monday.
It is not yet known whether the people involved are New Zealanders or whether they have been arrested.
The spokesperson said it is possible that police may have simply broken up a fight between protest groups.
Three-judge panel 'unusual' for case
A Japanese lawyer working in New Zealand says it is unusual that Mr Bethune is appearing before three judges - normally only people charged with serious crimes do.
Junichi Nishimura said a person facing the kinds of charges laid against the activist would normally appear before a single judge.
He believed the change has been made because the Japanese courts realise the case is an international matter.
Mr Nishimura said the Japanese justice system is very similar to New Zealand's.