Matti Saari was in police custody answering questions on Monday - 24 hours later ten people were dead.
The 22-year-old unleashed a killing spree at a college in the small provincial town of Kauhajoki in the west of Finland.
At around 11am yesterday, Saari arrived at the town's School of Hospitality, the vocational college where he was a culinary arts student. He walked into a class where an exam was in progress and opened fire. Mayhem broke out, and a short while later 10 students lay dead.
He then started two fires in the school before turning the gun on himself. He failed to kill himself outright but yesterday evening died in hospital — dashing hopes that he might shed light on his motives.
Last night Finland was in shock, and Kauhajoki, 200 miles north of the capital Helsinki, was struggling to come to terms with its grief.
Finnish police said last night that the gunman left notes saying he hated humankind.
He left two handwritten messages at the school dormitory saying he had planned the attack since 2002 and that he hated the human race, a police chief said.
The gunman had also written that the solution was a Walther 22, referring to the .22-calibre pistol he used in the attack.
The disclosure that Finnish police had called Saari in for questioning on Monday came as the extent of the carnage in the college emerged, and added to the sense of trauma.
The police had been acting on a tip-off that videos of Saari firing a gun at a range had been posted on the internet.
“Police reached him (Saari) on Monday 22 September,” Finland's Interior Minister Anne Holmlund admitted, “and asked him to be interviewed regarding the shooting video.”
Authorities checked his temporary pistol permit, which was in order. He had obtained it, along with his first pistol, only last month. The police then let him go without taking any other action.
A YouTube page believed to have belonged to Saari has clips showing him shooting a .22 calibre automatic pistol at a firing range and naming videos from America’s Columbine school massacre as among his favourites.
One of the clips is believed to have been uploaded just five days before the atrocity. In it the gunman — wearing a black leather jacket and black jeans — is seen shooting a handgun several times at an off-screen target.
In a different clip he is shown looking down at the camera and pointing a gun towards it.
“You will die next,” he says in English before shooting four times.
The page also includes what seem to be lyrics from a song called ‘War' from the work of German electronic music producer Wumpscut.
One part reads: “Whole life is war and whole life is pain, And you will fight alone in your personal war. War, this is war!”
Clips from the 1999 Columbine school shootings in Colorado where two youths killed 13 people then themselves were listed among his favourite videos.
The YouTube profile was removed yesterday.
It appears that the user last logged-in to the website only about an hour before the shooting. took place.
It was chillingly similar to a video posted on YouTube by 18-year-old secondary school student Pekka-Eric Auvinen before he went on to kill six students, his headmistress and a nurse at his school in Jokela, north of Helsinki, last November. Local detective superintendent at Kauhajoki Urpo Lintala, said: “It's a very great shock, a very sad case. “This is a small, quiet town with about 14,000 inhabitants. There's not much crime, it's very quiet around here. It's very peaceful, this is a very shocking case."
Matti Saari was training to be a chef.