According to one guy on a forum, the two others that were sighted in Breda were from the ALF and the other was from the international socialists. But the newspaper that filmed them doesn't want to cooperate with police. Noting is certain in that direction.
The BVD, the Dutch NSA, said from the beginning Volkert van der Graaf never did anything suspecious, but newspapers soon found out he was terrorizing farmers and freeing animals at night.
And now this other murder.
Also Peter R. de Vries, crime reporter, said this guy knew how to shoot. He told yesterday that he went to shoot 9mm on a range and said he wasn't able to hit 5 times in quick succession from a small distance like Volkert van der Graaf did.
Also Peter R. de Vries recieved hundered of email to investigate the case himself. De Vries also managed to prove the innocence of two man who were convicted wrongfully for rape and murder.
Also another politcian, the new leader of Livable Netherlands, Fred Teeven (a chief of police) said he wanted to supervize the police investigation.
I don't think the "animal rights" movement is about animals at all. It's about people, and making rules for people. Hence the passion, and the willingness to kill, to have their way.