German police have taken a 16-year-old Afghan youth into custody on suspicion that he was connected to the 18-year-old gunman who killed nine people in Munich on July 22.
The Afghan youth is being held for failure to notify authorities of a criminal act.
German police say the Afghan boy knew David Ali Sonboly, the young German-Iranian man who used Facebook to lure a group of young people to the McDonald's restaurant where the shooting started.
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A police statement said the Afghan youth is being investigated for his role in posting invitations on Facebook.
German authorities said on July 24 that Sonboly underwent two months of inpatient psychiatric treatment last year due to social anxiety and depression.
Thomas Steinkraus-Koch, a spokesman for Munich prosecutors, told reporters on July 24 that the 18-year-old suspect "received inpatient treatment in 2015 for two months and after that received outpatient care."
Steinkraus-Koch said the suspect suffered from "fears of contact with others" and also depression.
Bavaria police chief Robert Heimberger said on July 24 that the suspect had been planning the attack for a year.