When Jokela happened, I was working in IRC-Galleria, back then a hugely popular social media platform in Finland. Pekka-Eric had a profile too and also posted his manifesto onto its blog. We were quickly following the real time events through IRC (Internet Relay Chat) and I remember how someone had hid into the bathroom at Jokela school and texted their loved ones (which were also related to IRC) how scared they were and what sounds they were hearing. It was very quiet, apparently. As we found out the identity of this assailant, we immediately contacted the police and told them everything we knew. We hid his profile and the manifesto so it wouldn't be visible for anyone and especially the press, as we understood also the family of this man have to be protected. Police didn't know a lot about the case yet, they only knew some rumours and had received some calls from the school. Maybe. I have no real knowledge of that. But we ended up speeding up the investigation quite a bit and within just an hour or so after it had started.
Pekka knew Finnish police would not hesitate to come after him and he seemed to lack a real concrete plan, so the whole thing was over fast. Afterwards we held crisis chats to young kids at IRC-Galleria and kids all over Finland were scared to go to school. I was sitting in trauma chats for a week before the first shock was over and after that week it was us moderators that had to start working with our thoughts. It's never an easy task to take down profiles of the deceased. Not in the case of Jokela, not with Kauhajoki, not with Konginkangas accident or the Tsunami in Phuket. It's hard.
That is the one thing that I think should be important to know about this thing: social media was in key part in all things related to this event.
It was the place for Pekka to get his thoughts through, and it was the thing that gave police a suspect within an hour after first calls for help, while people were still terrorized by a mad gunman. And it has since been the place which stores his manifesto and lets it be an influence to copycats. I has been a place for healing, it has been a place for helping others heal and it continues to be all this to everyone willing to listen. In good, and in bad.