My Merriam-Webster's gives Nigerois, but apparently they consider this "something of an oversight.".    From Wordnik.com.  [languagehat.com: DOMINICA.] Reference

The two were found dead after a rescue attempt by Nigerois and French forces.    From Wordnik.com.  [NYT > Home Page] Reference

What’s more, Fitzgerald, aware, no doubt, of the weakness of the charges — mere perjury and obstruction, acts of omission rather than commission — and, perhaps, defensive about the tens of millions he’d spent to produce them, put on trial the “state of mind” that led the administration to sell the case for W.M.D., which, in turn, made it go a little batty when Joe Wilson started flapping about there being no deal between the Iraqis and the Nigerois for uranium, and hence no rationale for war (the lawyers and judge kept reminding the jury that, while it wasn’t supposed to judge the war, it could judge the “state of mind” that might have motivated the various players).    From Wordnik.com.  [Caught in the Spin Cycle] Reference