Beloit police are investigating two incidents over the last two days.  Multiple callers reported hearing shots fired just before 7:00 p.m. Monday in the 1600 block of Wisconsin Avenue.  Officers discovered three homes hit by bullets, and they recovered shell casings near the intersection of Dewey and Summit Avenues.  Police also report responding to a report of shots fired  about 10:30 p.m. Tuesday in the area of Hull and Yates Avenues.  Officers say nine shell casings were found, but no reports of damage or injuries.  Police are asking anyone with information about the crime to contact greater Beloit crime stoppers.