The nine, including three lieutenants and a captain, were arrested on Friday and Saturday as part of a probe into the death of the 47-year-old man at a police station last month.
Their arrests came amid at least two investigations into deaths in police custody and after President Abdel Fattah al-Sisi last week warned that police officers found guilty of "committing mistakes" would be punished.
The official MENA news agency said the arrests were ordered after a forensic report revealed that the man had died after being beaten on his neck and back.
The man had been arrested on November 26 from a cafe in southern city Luxor and taken to the police station where he died an hour later.
Also Read
Another police officer has been detained in a separate case of a veterinarian who died in police custody last month in the Suez Canal city of Ismailiya.
Rights groups regularly accuse Egyptian police and members of the intelligence services of abusing and torturing detainees.
Police abuses under former president Hosni Mubarak were a key factor for the 2011 revolt that led to his ouster.
Saeed's death galvanised protests against Mubarak after pictures emerged online of the 28-year-old's mangled face.
Egypt was under military rule for 17 months after Mubarak's overthrow and the police kept a low profile.
Islamist Mohamed Morsi then became Egypt's first freely elected leader but was overthrown by then-army chief Sisi in 2013, who has launched a brutal crackdown on his supporters.