It is narrated from Sayyiduna al-Sa'ib bin Khallad (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever frightens the people of Madinah, upon him is the curse of Allah, the angels and all the people."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6602