Horns of Shaitaan

Imam Bukhari has quoted this Hadith from Abdullah Ibn Umar (رضئ اللہ تعالی عنہ) that Prophet (صلى الله عليه و آله وسلم) once prayed for Syria and Yemen. It is narrated that there were some people of Najd also present in the gathering and they requested the Prophet (صلى الله عليه و آله وسلم) to make supplication (du’a) for Najd also. Prophet (صلى الله عليه و آله وسلم) continued saying: ‘O! Allah, Shower Blessings on Syria and Yemen’. The people of Najd again requested the Prophet (صلى الله عليه و آله وسلم) to offer prayers for Najd. The Prophet (صلى الله عليه و آله وسلم) said: ‘It is a place of tremor and mischief (Fitna) and the Horn of Shaitaan will rise from there.’ 
[Sahih Bukhari, Vol – ii, P – 1050].