Help identify please

While sitting beside my wildlife pond today I saw something in the water (at least 2 of them) As they moved quite quickly I didn't get too good a look.
The nearest way I could descibe them were a cross between a slug and a leech, but with lots of little legs. As they surfaced they seemed to have a sucker type mouth like a leech. Can't find them in any of my books.
Any one know what they might have been.

 

Cichlid-Forum :: View topic - looks like leech, with legs DRIVING ME CRAZY!!! what is it? ive no idea x

 

could also be fly larvae our ponds are full of midgie ,and other such larvae some look like leeches with sucker mouths look up pondlife larvae you`ll see what i mean i gather nets full each day and feed to my fish (fish tank in house)also gather caterpillars and slaters the fish love them

 

Thanks for your help. I'll look up Lavae site. I had been looking up pond insects and couldn't come up with anything.