Last year, 15 people were fatally shot by Philadelphia police.
Goode and Cephas were armed when they raised their guns prompting officers to fire, according to Lt. Frank Vanore.
The families of the deceased say both men were wrongfully killed.
Former Mayor Goodeappealed for calm.
"There's a half-dozen versions of events out there, and that's why everyone needs to wait until the investigation is complete and witnesses are interviewed and the film is reviewed," said the former mayor, now a Baptist minister.
"The mayor has promised he will do that, and I have confidence he will."
With crime his No. 1 issue, Mayor Nutter - who spoke with Goode and his son, Councilman W. Wilson Goode Jr. - vowed a "full and proper investigation of that shooting, and every shooting in Philadelphia."
But Nutter also warned: "If you point a weapon at any police officer, or law-enforcement person, there's a high probability you will get shot."
Now, after only a week on the job, Police Commissioner Charles H. Ramsey is confronted twice with the use of deadly force by police. Last night, Ramsey said he would review both cases, and possibly have a news conference today.
Ramsey said that Timothy Goode had some guns registered to him, but no permit to carry them.
The commissioner, who was packing at his Washington, D.C., home last night to move here, could not recall whether Goode's 9 mm handgun, recovered by police, was registered.
Vanore said that at 9 p.m. Friday, undercover drug cops saw two males conducting "numerous" narcotics transactions on Clapier Street near Wayne Avenue.
At 9:23 p.m., an officer ordered them to stop. Officers arrested Stephan Siler, 27, of Abbottsford Avenue near Pulaski, for drug violations without incident.
