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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The incident happened at around 1.30pm on Saturday March 18 when the victim was walking her dog in Chaddesden Park, Derby.
The swan would not move off the carriageway and the northbound slip road at Junction 28 was closed for a short time.
Unsettled through the rest of the week.