"I said to Bilal: 'How did the Prophet (S) reply to them when they gave him Salams and he was performing Salat?' He said: 'He would motion with his hand.'" (Using translation from Tirmidhī 368)
قُلْتُ لِبِلَالٍ كَيْفَ كَانَ النَّبِيُّ ﷺ يَرُدُّ عَلَيْهِمْ حِينَ كَانُوا يُسَلِّمُونَ عَلَيْهِ فِي الصَّلَاةِ؟ قَالَ كَانَ يُشِيرُ بِيَدِهِ