A mystery 'river monster' has been hunting birds in the waters around the Olympic Park - and there are now calls for the Environment Agency to investigate.
Six years ago there were fears that a large predator was lurking in the murky depths.
At the time, some experts speculated that a giant turtle could be responsible, but before the mystery could be solved, the beast disappeared.
But now it seems to be back.
Mike Wells, a boat-dweller living on the River Lea in East London, was sitting on his barge last week when he saw a large Canada goose suddenly disappear into the water.
He said: "We were just passing the time of day looking at a Canada goose 30 yards away, but then it just suddenly disappeared.
"It went down vertically. There wasn't any hesitation, it went straight down. It didn't come back up. My friend and I looked at each other slack-jawed.
"Being a river person, I pieced together what we'd seen in seconds. The goose was prey to something.
"A Canada goose is not a small bird. They weight about 16lb, so whatever took it was also large."
Mike later discovered several other incidents from 2005 when there was speculation that a crocodile might have taken up residence in the River Lea.
What could it be?
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