It is narrated from Ziyad, who was a freed slave of Banu Makhzum and was trustworthy: A group of people hunted while in the state of Ihram, so Ibn Umar (may Allah be pleased with them both) said to them: "A penalty (fidyah) is obligatory upon you." They asked: "Is a separate penalty obligatory upon each one of us, or is there only one for all of us?" Ibn Umar (may Allah be pleased with them both) replied: "Not as it is commonly known among you, rather only one penalty is obligatory upon all of you."
Hadith Referenceمسند الإمام الشافعي / كتاب الحج / 891
Hadith Takhrijصحيح: اخرجه البيهقي في المعرفة السنن والآثار (3205) - وعبدالرزاق (8357) - والدارقطني : (2/ 250)۔