WHO lives in a hole like this, was the question on everyone's lips after rumours that a crocodile is snacking on wildlife from the Old River Lea.

Armed with nothing more than a notebook, pen and camera Guardian staff took their lives in their hands on a boat trip up river to the site of the Olympic regeneration park on the Leyton border with Stratford to find clues.

National newspapers and London radio stations snapped up our exclusive story two weeks ago.

We reported that evidence, including large holes on the river bank, suggests a crocodile or alligator could be responsible for the mysterious disappearance of large birds including a Canada goose and five cygnets. Fishermen have also said dogs have vanished from the tow paths.

But the hunt is on to find out exactly what is lurking in the depths.

We set off up river from Bow Locks with Mark Gallant, conservation officer with the Lea Rivers Trust, who witnessed the attack on the Canada goose, and his crew, rivers officers Tim Pegg and Mike Heron.

Mr Gallant said: "Put it this way, whatever it is must be big and fast. One minute the bird was there and then it was gone. Never to be seen again.

"We've also seen large holes in the river bank."

The goose met its demise a short distance upstream from the site of the future Olympic stadium, an area which has no public access.

We saw for ourselves that large holes, up to one-metre wide and set in the mud, would be perfect spots for a crocodile to bask.

Overhanging branches and shadowy shallows also provide perfect cover for a predator stalking its prey.

Anticipation was running high as we turned off the motor and drifted up the delta.

Mr Pegg steadily guided the boat under the trees and closer to the beast's lair, and Mr Heron bravely donned his waders to pull us further into the unknown.

Suddenly, a splash just a few feet from the boat raised everyone's expectations.

The sun flashed off the water and we quickly scanned its surface. Could this be the moment we had been waiting for?

A quick glance from Mr Gallant revealed that the river was home to at least one exotic creature, a red eared terrapin.

He said: "We have found terrapins along the rivers before and it's interesting that they have settled here. They were probably exotic pets that people decided they didn't want to keep. The question is, if they can manage to live here, is it possible for something like a crocodile or alligator to make it their home?"

We investigated the holes and after closer inspection we were still no nearer to the truth.

Mr Gallant added: "The truth is out there somewhere and we'll keep looking. I've seen so many unusual things in the river that it really would not surprise me if turned out to be crocodile or alligator."