VERY VERY IMPORTANT.

Cut the breaker off in that area before you do any work.

Okay just cut the cords with a solid hard based wire cutter and with plastic or rubber handles. Make sure you are wearing gloves.

After cutting the wires buy electrical wire caps and cap the live wire off. Turn the breaker back on and you'll be done.

Just be sure to cut the breaker off otherwise you will experiences shocks , electrocutions, burns, and/or death.