The Glasgow derby took place at 12pm on Sunday and resulted in a 3-3 draw.
Police said no arrests were made at Ibrox Stadium, but a small number of reports relating to hate crimes are currently being assessed.
We previously reported that an object was thrown and struck a man, but he did not require medical attention.
A Police Scotland spokesperson said: “We are aware of an object being thrown at Ibrox Stadium, Glasgow, during the Rangers v Celtic match on April 7.
“One man was struck but did not require treatment and inquiries are ongoing.”