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Abu Sa'id Khudri reported Allah's Messenger (ﷺ) having said: There is a group of jinns in Medina who accepted Islam, so he who would see anything from these occupants should warn him three times; and if he appears after that, he should kill him for he is a satan.
Source: sunnah.com
Other translations
Arabic
وَحَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنِ ابْنِ عَجْلاَنَ، حَدَّثَنِي صَيْفِيٌّ، عَنْ أَبِي السَّائِبِ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ، قَالَ سَمِعْتُهُ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنَّ بِالْمَدِينَةِ نَفَرًا مِنَ الْجِنِّ قَدْ أَسْلَمُوا فَمَنْ رَأَى شَيْئًا مِنْ هَذِهِ الْعَوَامِرِ فَلْيُؤْذِنْهُ ثَلاَثًا فَإِنْ بَدَا لَهُ بَعْدُ فَلْيَقْتُلْهُ فَإِنَّهُ شَيْطَانٌ " .
sunnah.com