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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Generally dry later with a mild dawn following despite clearing skies.
Showers will slowly ease through this evening and will turn dry overnight.
Mainly dry during the evening with low cloud breaking to give late sunny spells.