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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Cold with some icy stretches to start. There will be sunny intervals and further blustery, wintry showers.
Early wintry showers will clear to give a mostly dry day with some sunny spells.
Scattered wintry showers will continue overnight. Clear spells will allow a frost to develop by morning.