According to a police in the town of Kamp-Lintfort just northwest of Duisburg, the 60-year-old driver resorted to restraining the child on Friday when he refused to stop running around.
“After the boy repeatedly refused to take a seat and continued to run uncontrollably through the bus, the driver tied the boy temporarily to a seat to insure his safety during the ride,” a statement said.
A friend eventually untied the unruly boy, who later followed the driver's rules, the statement added.
But on Tuesday the head of the bus company Heinz-Jakob Ohlenforst announced the driver had been fired.
“His behaviour was not acceptable, even if he's now sorry,” he said.
Meanwhile the boy's parents have filed a complaint against the driver for deprivation of liberty.
“The investigation is in full swing,” a police spokesperson told news agency DDP.