He said their aim was to keep the peace and put off any would-be criminals.
Keenan said Sundays were possibly busier than other days as people were getting over socialising at the weekend including drinking alcohol, consuming drugs and spending money.
He said criminals also targeted hot spots on this day because generally there tended to be more people out and about.
"A lot of things really get busy on Sundays sadly, particularly family violence and driving offences."
Keenan said four police officers would work on the unit during the day on Sunday and would be rostered from different policing groups that didn't already work on the frontline, including youth aid, CIB and family violence.
The unit will work as a trial until at least April next year.
"This unit supports the frontline capability in ensuring proactive crime prevention and visibility across our city while our frontline staff continue with their response."