A teenaged terrorism suspect detained in the German city of Cologne was recruited by the Islamic State militia via online chat groups and encouraged to plant a nail-filled bomb, local media reported Friday.
According to reports citing the arrest warrant, the 16-year-old Syrian refugee was instructed to place the bomb in a trash bin in a well-trafficked public place.
He afterwards was heard in a mosque saying that he wanted to kill for the Islamic State group.
Investigators are now in the process of evaluating and translating the chats, a spokesman for the state's attorney's office said. This could take some time, he said, as it requires analysis of a "not inconsiderable amount of data" from the suspect's mobile phone.
The 16-year-old asylum seeker was taken into custody Wednesday in the Porz district of Cologne, where he was living in refugee accommodation.
The suspect expressed "unequivocal willingness" to commit a bomb attack in online chats, Cologne police spokesman Klaus-Stephan Becker said during a press conference.
Police chief Juergen Mathies added that the teen had received "very concrete directions" on how to build an explosive device, but that there was no evidence to suggest he already possessed the necessary materials.
Officials said an evaluation of the boy's mobile phone showed he had been in contact with an Islamic State operative located outside Germany and that he had been radicalized within a short period of time.
The teenager fled the war in Syria with his parents and sister and was first registered on January 4, 2015.
He came to the attention of police in June, when his behaviour was said to have changed markedly. Following a second check by police, the decision was made to detain him.
Germany has been on high alert since two terrorist attacks occurred in the space of one week in July. Both were claimed by the Islamic State group and carried out by asylum seekers.