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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It will start grey and murky again with extensive low cloud. Becoming brighter with some warm sunshine later.
Turning murky again overnight. Showers possible in the south.
Walmley in the West Midlands would become the new centre of Great Britain if Scotland vote to go independent, Ordnance Survey has said.