GUST Expedition (2001)
Mystery Casebook A controversial expedition by the Global Underwater Search Team (GUST) was conducted with advanced sonar equipment to search for the creature. One night, a small sonar contact moved on the screen. On another occasion, a vague disturbance was captured on film.

The expedition was shown on a program called Loch Ness Monster: Search for the Truth.

Television investigations (2003-4)

In July 2003, the BBC reported on an extensive investigation of Loch Ness by a BBC team using 600 separate sonar beams to ensure that none of the loch's waters were missed. The expedition found no trace of a "sea monster" or any other large animal in the loch. The BBC team concluded that Nessie simply did not exist.

Source & References:

http://en.wikipedia.org/wiki/Loch_Ness_Monster

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