Hazrat Umair bin Anas narrates that my Ansari uncles, who were among the companions of the Prophet (peace and blessings be upon him), informed me that the Shawwal moon was hidden from us (due to clouds, etc.), and so we kept the fast in the morning. Later in the day, a group of horsemen arrived and presented themselves before the Prophet (peace and blessings be upon him) and testified that they had seen the moon the previous day. So the Prophet (peace and blessings be upon him) ordered the people to break their fast and commanded them to go out for Eid the next day. And (Imam) Abu Hanifa's opinion has been mentioned that: on the next day, people should not go out for Eid.