A New Zealand anti-whaling activist who boarded a Japanese harpoon ship has been charged with five offences, including trespass and causing injury.
Pete Bethune, of the Sea Shepherd Conservation Society, boarded the Shonan Maru 2 in February, and tried to make a citizen's arrest of its captain.
The incident happened as Sea Shepherd activists attempted to disrupt Japan's annual whale hunt in Antarctic waters.
If found guilty, Mr Bethune could face up to 15 years in prison.
Mr Bethune had been in command of Sea Shepherd's hi-tech speedboat, the Ady Gil, when it was sliced in two in a collision with the Shonan Maru 2 in January. All six crew members escaped unharmed.
On 15 February, Mr Bethune boarded the Shonan Maru, saying he wanted to arrest its captain, Hiroyuki Komiya, and present him with a bill for the damage.
He was detained on the ship and taken to Japan, where he was formally arrested for trespass earlier this month.
A spokeswoman at Tokyo's District Court said he had been charged with "trespassing, causing injuries, obstructing commercial activities, vandalism and carrying a weapon", reported to have been a knife.
Chief Cabinet Secretary Hirofumi Hirano said Japan would "strictly deal with such cases under the law", the AFP news agency reported.
The BBC's Roland Buerk in Tokyo said it could be several months before Mr Bethune's case is heard in court but that he will be hoping the trial will bring Japan's whaling industry under further scrutiny.
The crew of the Shonan Maru said the activists had tried to tangle a rope in their propeller and had thrown butyric acid at the ship, giving a "chemical burn" to one sailor.
But Sea Shepherd has denied any of its activists caused injury and said the substance thrown was harmless, if unpleasant, rancid butter.
The Ady Gil incident was one of several clashes between Japan's whaling fleet and Sea Shepherd activists in the Southern Ocean during the hunt season.
The group has described Mr Bethune as a "political prisoner" and says the charges against him are bogus.
"Shame on Japan for blowing Captain Bethune's case out of proportion, and shame on Japanese maritime authorities for failing to investigate the serious criminal actions of the Shonan Maru 2," it said, in a statement.
It also accused New Zealand of being "surprisingly quiet" on the arrest.
The charges come a day after New Zealand's representative on the International Whaling Commission said countries should be allowed to kill a limited number of whales.
Sir Geoffrey Palmer said attempts to reach a global deal on whaling would fail unless nations could compromise.
Japan abandoned commercial whaling in 1986 after agreeing to a global moratorium - but international rules allow it to continue hunting under the auspices of a research programme.
It says the annual hunt catches mostly minke whales, which are not an endangered species.
Conservationists say the whaling is a cover for the sale and consumption of whale meat.