Washington, Aug 5 (AFP): NASA scientists announced today that they had found the first evidence of flowing water on Mars.

If confirmed, the evidence gathered by the Mars Reconnaissance Orbiter would be the first discovery of active liquid water in the ground on the red planet.

"We have found repeated and predictable evidence suggesting water flowing on Mars," Michael Meyer, lead scientist for the Mars Exploration program, told reporters.

The US space agency said the orbiter circling Mars since 2006 had monitored numerous instances of what appeared to be water flows occuring in several locations during the Martian spring and summer.

Time-sequence imagery of the Newton crater in the southern mid-latitude region showed finger-like markings spreading along several steep slopes and then fading again once colder temperatures move in.

"The best explanation we have for these observations so far is flow of briny water, although this study does not prove that," said Alfred McEwen of the University of Arizona's Lunar and Planetary Laboratory.

"It's a mystery now, but I think it's a solvable mystery with further observations and experiments," said McEwen, lead author of a study explaining the findings in the journal Science.

NASA experts are still not sure if what they have witnessed is actually water flowing on Mars, where no liquid water has been found to date.