Originally Posted by Doug Stirling

Steve, I would suspect that the aux drive belt has snapped or glazed over badly.

This grooved poly-V belt drives the power steering pump and water pump, and either of those could have siezed initially causing the screeching noise. If you had low power steering fluid, or a sudden loss of all the power steering fluid it may well cause the problem described.

Remove the top part of the black plastic cambelt cover to check the aux drive belt.