The man suspected of carrying out a mass stabbing attack that left 19 people dead at a Japanese care home for the mentally disabled has been moved from a local police station to the prosecutor's office in Yokohama.
Satoshi Uematsu, 26, his head and shoulders covered with a blue jacket, was led out of a police station in Sagamihara city and into the back of an unmarked white van with emergency lights.
Photographers and video journalists surrounded the van as it pulled away.
Uematsu had been held at the police station all day and overnight after turning himself in about two hours after Tuesday's pre-dawn attack. He had earlier delivered a letter to parliament outlining the bloody plan and saying all disabled people should be put to death.
Kanagawa regional authorities said Uematsu had left dead or injured nearly a third of the nearly 150 patients at the centre in a matter of 40 minutes.
It is Japan's deadliest mass killing in decades. The fire brigade said 25 were wounded, 20 of them seriously.
Security camera footage played on TV news programmes showed a man driving up in a black car and carrying several knives to the Tsukui Yamayuri-en centre in Sagamihara, 30 miles west of Tokyo.
The man broke in by shattering a window at 2.10am, according to a health official, and began slashing the patients' throats.
Sagamihara fire brigade official Kunio Takano said the attacker killed 10 women and nine men. The youngest was 19, the oldest 70.
Details of the attack, including whether the victims were asleep or otherwise helpless, were not immediately known. Kanagawa welfare division official Tatsuhisa Hirosue said many details were not clear.
Uematsu had worked at Tsukui Yamayuri-en, which means mountain lily garden, from 2012 until February, when he was let go. He knew the staffing would be down to just a handful in the early hours of the morning, news reports said.
The care centre employs more than 200 people, including part-timers, with nine of them working on the night of the attack, Mr Hirosue said. All those killed were patients.
"They were working at night and were questioned by police after witnessing graphic violence, making them a little emotionally unstable now," he said.
In February, Uematsu tried to hand deliver a letter to parliament's lower house speaker that revealed his dark turmoil. It demanded that all disabled people be put to death through "a world that allows for mercy killing", Kyodo news agency and TBS TV reported. The parliament office also confirmed the letter.
Uematsu boasted in the letter that he had the ability to kill 470 disabled people in what he called was "a revolution" and outlined an attack on two centres, after which he said he would turn himself in.
He also asked he be judged innocent on grounds of insanity, be given 500 million yen in aid and plastic surgery so he could lead a normal life afterwards.
"My reasoning is that I may be able to revitalise the world economy and I thought it may be possible to prevent World War III," the letter says.
The letter was delivered before Uematsu's last day of work at the centre, but it was unclear whether the letter played a role in his sacking, or even if his superiors had known about it.
The letter included Uematsu's name, address and telephone number, and reports of his threats were relayed to local police where Uematsu lived, Kyodo said.
Kanagawa governor Yuji Kuroiwa apologised for having failed to act on the warning signs.
Some people in the area said they were shocked that Uematsu is accused, and described him as polite and upstanding.
Akihiro Hasegawa, who lived next door to Uematsu, said he heard he had been in trouble with the centre, initially over sporting a tattoo, often frowned upon in mainstream Japanese society because of its association with criminal groups.
"He was just an ordinary young fellow," he said.
Mass killings are rare in Japan. Because of the country's extremely strict gun control laws, any attacker usually resorts to stabbings. In 2008, seven people were killed by a man who slammed a lorry into a crowd of people in central Tokyo's Akihabara electronics district then stabbed passers-by.
In 2001, a man killed eight children and injured 13 others in a knife attack at a primary school in the city of Osaka. The incident shocked Japan and led to increased security at schools.
This month, a man stabbed four people at a library in north-eastern Japan, allegedly over their mishandling of his questions. No one was killed.