A 16-year-old friend of the gunman who killed nine people in Munich on Friday has been arrested by police.
Investigators say the teenager is suspected of knowing about David Ali Sonboly's planned attack and failing to report it.
Munich Police added that the arrested youth may have played a role in a Facebook post, which invited people to the McDonald's restaurant where the shooting unfolded.
The 18-year-old suspect, who killed himself, had an obsession with shooting sprees and had received psychiatric treatment for depression.
Tonight hundreds of mourners have gathered near the scene of Friday's shooting to lay flowers and light candles.