The United States sends letter to ISIS , stressing dam 's strategic importance . CNN 's Barbara Starr , Ali Younes , Mohammed Tawfeeq , Alexander Felton , Mariano Castillo and Fredricka Whitfield contributed to this report . ISIS wants to keep Peshmerga working , Congress analyst says . Mosul Dam spokesman : Forces have retaken one side of the dam . Smoke rises from the horizon , and buildings are ablaze in the battle to retake it .
The United States sends letter to ISIS , stressing dam 's strategic importance . ISIS wants to keep Peshmerga working , Congress analyst says . Mosul Dam spokesman : Forces have retaken one side of the dam . Smoke rises from the horizon , and buildings are ablaze in the battle to retake it .