The presence of spearmen (with their spears) in the mosque (is permissible)
باب أَصْحَابِ الْحِرَابِ فِي الْمَسْجِدِ
Sahih al-Bukhari, Book of Prayers (Salat)(view book)
Sahih al-Bukhari 454
Narrated 'Aisha:
Once I saw Allah's Apostle at the door of my house while some Ethiopians were playing in the mosque (displaying their skill with spears). Allah's Apostle was screening me with his Rida' so as to enable me to see their display. ('Urwa said that 'Aisha said, "I saw the Prophet and the Ethiopians were playing with their spears.")
حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، عَنْ صَالِحٍ، عَنِ ابْنِ شِهَابٍ، قَالَ أَخْبَرَنِي عُرْوَةُ بْنُ الزُّبَيْرِ، أَنَّ عَائِشَةَ، قَالَتْ لَقَدْ رَأَيْتُ رَسُولَ اللَّهِ ﷺ يَوْمًا عَلَى باب حُجْرَتِي، وَالْحَبَشَةُ يَلْعَبُونَ فِي الْمَسْجِدِ وَرَسُولُ اللَّهِ ﷺ يَسْتُرُنِي بِرِدَائِهِ، أَنْظُرُ إِلَى لَعِبِهِمْ. زَادَ إِبْرَاهِيمُ بْنُ الْمُنْذِرِ حَدَّثَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، قَالَتْ رَأَيْتُ النَّبِيَّ ﷺ وَالْحَبَشَةُ يَلْعَبُونَ بِحِرَابِهِمْ.