Sahih al-Bukhari 76:45
Narrated `Abdullah bin 'Amir:
`Umar went to Sham and when he reached Sargh, he got the news that an epidemic (of plague) had broken out in Sham. `Abdur-Rahman bin `Auf told him that Allah's Messenger (ﷺ) said, "If you hear that it (plague) has broken out in a land, do not go to it; but if it breaks out in a land where you are present, do not go out escaping from it."
Reference
Sahih al-Bukhari 76:45
In-book reference
Book 76, Hadith 45
Arabic Text
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَامِرٍ، أَنَّ عُمَرَ، خَرَجَ إِلَى الشَّأْمِ، فَلَمَّا كَانَ بِسَرْغَ بَلَغَهُ أَنَّ الْوَبَاءَ قَدْ وَقَعَ بِالشَّأْمِ، فَأَخْبَرَهُ عَبْدُ الرَّحْمَنِ بْنُ عَوْفٍ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا سَمِعْتُمْ بِهِ بِأَرْضٍ فَلاَ تَقْدَمُوا عَلَيْهِ وَإِذَا وَقَعَ بِأَرْضٍ وَأَنْتُمْ بِهَا فَلاَ تَخْرُجُوا فِرَارًا مِنْهُ ".