Finnish police yesterday arrested—and subsequently released—the 20-year-old they say killed 11 people, including himself, during a school shooting spree this morning, reports the Daily Telegraph. Authorities acted after finding a YouTube video of Matti Juhani Saari firing a handgun at a shooting range, and this posted message: "Whole life is war and whole life is pain. And you will fight alone in your personal war." (More Finland school massacre stories.)