Two years ago, researchers reported the discovery of a saltwater lake under the icy poles of Mars. This has now been confirmed.
Salty Lakes Below Mars' Glaciers Could Harbor Life
Even more salty lakes found under Mars' south pole - The Weather Network
Seeing red: Researchers uncover the century-old mystery of Blood Falls
Lake Found on Mars - Antarctica Journal
Underground Lake Found on Mars? Get the Facts.
Mars has a giant hidden lake. Could there be life in it?
Confirming Presence of Large Subglacial Lake on Mars's South Pole, Scientists Find Three New Salty Ponds
Subsurface lakes raise new questions about life on Mars
Salty lakes found beneath Mars' surface
Mars: huge underground lake raises prospects of life on planet, astronomers say, Mars