Hexenjagd (literally German: "witch hunt") are a group of scientists and other personnel formerly affiliated with The Organization.
Hexenjagd are first mentioned by name when series protagonist Ryouta Murakami, who reads the name on a PDA given to him by Neko Kuroha, an escaped "witch", or a human given superpowers by an implanted alien parasite. Four members of Hexenjagd appear in person much later in the anime and manga, when they enter the observatory where Murakami has been hiding several escaped "witches", and confront Murakami and the escapees, as well as the recently arrived Chisato Ichijuku and Mako Fujisaki. Using a member capable of nullifying the powers of witches, they suppress Mako's abilities, and state the "witches" are actually controlled by personalities implanted on the parasites, and will transform into monsters that prey on humans when they hatch. As such, they intend to kill all "witches". At the moment, however, they state that they only intend to eliminate Kotori Takatori, a "witch" implanted with a special type of alien called a Grane, which, if it hatches, could destroy the entire planet. Ichijuku ends the stand off when he wounds the ability-suppressing member with a handgun, and Fujisaki teleports away both herself, Ichijuku, and Kotori.
Hexenjagd and Murakami's group are forced to join forces, as, at the moment, both seek to find Kotori, though for very different reasons. Kazumi Schlierenzauer, a technopathic "witch" living with Murakami manages to hack into the servers of The Organization, despite opposition from Freya, and locates where Chisato is holding Kotori, who is revealed to actually be his own sister, Rena, and the only person the misanthropic Chisato ever cared about. Ichijuku intends to activate the Grane, believing doing so will revive his sister and make the two of them essentially gods.
Ichijuku is almost successful, but Kotori tells Ryouta to press the "eject" button on the harness, or implant in the back of her neck, killing both Kotori and the Grane. With her last words, Kotori reveals that she was concious of her identity Rena all along, but did not approve of his methods to revive her, which cost countless lives. A despairing Ichijuku promised to never harm another human again, and dedicate his life to saving lives.
After the death of Kotori, Hexenjagd attempt to shoot Mako, having suppressed her powers, but only for seven seconds. Chisato, however, jumps in front of the bullets, sacrificing himself to save her and making good on his promise to his dying sister. Long, one of the Hexenjagd agents attacks Mako with his combat knife, having expended his submachine gun's magazine on Chisato. Mako, however, by this point regains her powers and tears off Long's arm, before announcing her intend to destroy all life on earth, starting with Ryouta, the witches, and Hexenjagd.
Mako's destructive plans, however, are stopped by Neko Kuroha, who, using hitherto latent powers, defeats Mako in combat. After Mako's defeat, Hexenjagd give Ryouta the ingredients to the "death suppressant" drugs that "witches" must take to survive in exchange for the aid of his "witch" allies.
Equipment and Uniforms
For unknown reasons, all Hexenjagd agents wear uniforms vaguely similar to the attire of Catholic priest and nuns, possibly because of the historical association of the medieval and Renaissance-era churches with "witch hunts". The primary weapon used by members of Hexenjagd is a Heckler & Koch MP5 submachine gun, though at least Long is also armed with double-edged combat knife similar to a Fairburn-Sykes Commando fighting knife. As they were responsible for the destruction of a the armored convoy from which Neko Kuroha and the other witches escaped, it can be assumed that they also have access to heavier anti-vehicle weapon such as rocket launchers or mines.