If a dead body or a polluted thing is put on the back of a person offering Salat (prayer), his Salat will not be annulled (rejected by Allah)

Sahih al-Bukhari · Book 4 · Hadith 240

حَدَّثَنَا عَبْدَانُ، قَالَ أَخْبَرَنِي أَبِي، عَنْ شُعْبَةَ، عَنْ أَبِي إِسْحَاقَ، عَنْ عَمْرِو بْنِ مَيْمُونٍ، عَنْ عَبْدِ اللَّهِ، قَالَ بَيْنَا رَسُولُ اللَّهِ صلى الله عليه وسلم سَاجِدٌ ح قَالَ وَحَدَّثَنِي أَحْمَدُ بْنُ عُثْمَانَ قَالَ حَدَّثَنَا شُرَيْحُ بْنُ مَسْلَمَةَ قَالَ حَدَّثَنَا إِبْرَاهِيمُ بْنُ يُوسُفَ عَنْ أَبِيهِ عَنْ أَبِي إِسْحَاقَ قَالَ…

Narrated `Abdullah: While Allah's Messenger (ﷺ) was prostrating (as stated below). Narrated `Abdullah bin Mas`ud: Once the Prophet (ﷺ) was offering prayers at the Ka`ba. Abu Jahl was sitting with some of his companion…