The uncle of Sa'd bin Ishaq (the son of Sayyiduna Ka'b bin Ujrah (may Allah be pleased with him)) said: On the day of Eid I went out with my father to the Eid prayer ground, and he was one of the Companions of the Prophet (peace and blessings be upon him). He sat down before the imam came and did (nothing else) until the imam left. Then, when the people returned, they began going towards the mosque in rows upon rows. I said to him: Do you not see the people? He said: "This is an innovation and an abandonment of the Sunnah."
Hadith Referenceالمعجم الكبير للطبراني / باب الكاف / 16377