Bring Prospector Anvilward's Head to Aeldon Sunbrand at Falconwing Square in Eversong Woods.
Listen, [player]. This is a very delicate situation; even though we've identified the spy, we cannot kill him out in the open. We cannot try to capture him either as the risk of him escaping is too great.
I want you to go find Prospector Anvilward at the North Sanctum and kill him. Do this in a quiet manner, we don't want word to spread that we allowed a spy into our city.
Bring me his head as proof. Ironforge will learn not to meddle with the sin'dorei.