Staffordshire Police say they have arrested four youths in connection with a knifepoint of a 66-year-old man.
A 12-year-old, two 14-year-olds, and a 15-year-old have been arrested on suspicion of robbery. They all remain in police custody.
The elderly man, who cannot swim, was pushed into the canal by Middleport Pottery during the incident.
He was taken to hospital after being helped out of the water, but did not suffer serious injuries.
Chief Inspector John Owen said on Twitter: “We have today arrested four males in relation to the knifepoint robbery where a 66-year-old man was pushed into the canal.”
The incident happened on Saturday shortly after midday, on Sunny Bank, off Newport Lane in Middleton.
The victim, who was walking along the Trent and Mersey canal from Westport Lake towards Etruria near Middleport pottery, had a quantity of money taken from him during the incident.