Supt Kevin Purcell, of West Mercia Police has said four children were playing near the lock, but two fell in and another then went to try and get them out, while the fourth ran home to raise the alarm.
This video shows the canal where three children entered the water. Police say they are 'working hard to establish exactly how Imie came to be in the water'.
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Most parts across the region will be dry but showers are likely as well as brisk winds.
30 firefighters are currently at the scene on Aston Church Road in Nechells. People are being asked to avoid the area.
Goal-scoring recordbreaker Vardy has started every game in Leicester's rise to the top of the league.