Mourners are laying flowers near the scene of the deadly Christmas market attack as investigators puzzle over the motive of the suspect and his previous encounters with authorities are scrutinized

The Johanniskirche, a church located just a short distance from where the attack unfolded, has emerged as the focal point for mourners since Friday evening's tragedy, when a car plowed into the bustling Christmas market, claiming five lives. The sidewalk outside the church is now blanketed with a sea of flowers, a somber tribute to the victims.