Hadith.2037 - It is narrated from Muhammad ibn Qays, from Abu Ja'far (as), who said
"If two witnesses testify before the Imam that they have seen the crescent moon thirty days ago, the Imam commands the people to break their fast on that day if the testimony is given before noon. However, if they testify after noon, the Imam commands them to break their fast on that day but delays the Eid prayer until the next day, and then he leads them in prayer."