A Russian lawyer has admitted killing his colleagues because of unrequited love and hatred towards humanity.
Dmitri Vinogradov, 29, went to the office of local pharmacy chain Rigla in Moscow on Wednesday with two shotguns and a uniform hidden in his backpack.
He had been working as a lawyer for the company since 2008 so security staff did not check him when he entered the building.
Vinogradov changed his clothes in a toilet, loaded his weapons and ran into the finance department, greeted his colleagues and began shooting everyone in the room in the head.
Six people died in the rampage, and another victim is still fighting for her life in hospital.
He was eventually overpowered by security guards while attempting to reload his weapons. He was found with 230 shotgun cartridges in his backpack.
Anna Kaznikova, the girl thought to be the cause of Vinogradov's frustration, told the Metro newspaper their relationship was purely platonic and that she stopped seeing him after he became increasingly possessive and aggressive.
According to investigators, he also admitted drinking for five days in a row before the shooting.
Vinogradov published a manifesto hours before the shooting on his page on the Russian social network website vKontakte.
In this document, he compared humanity to cancer and wrote that he hated society and life and the only way to justify his existence was to destroy as many units of "human fertiliser" as possible.
His page is still open and his manifesto has received 7,000 "likes" from other users.
Former colleagues said they never heard him express radical views, but his Vkontake page contains neo-Nazi posters.
According to his mother, Yelena Vinogradova, he was suffering from depression after the breakup and was taking medication.
She said: "He bought Anna a trip to Edinburgh, booked everything, paid for everything, and two days before he said 'I am not going anywhere'."
Vinogradova said after breaking up with his girlfriend he bought a rifle and went to shooting ranges outside Moscow to practice.
The ruling United Russia party has called for the computer game Manhunt, which Vinogradov is believed to have enjoyed playing, to be banned.