Mr Lewis (24) was shot and fatally injured on Reginald Street in the Chapeltown area of Leeds on Wednesday, August 1 at around 7.15pm.
A 38-year-old man has been arrested on suspicion of murder and a 26-year-old male has been arrested for assisting an offender.
A total of nine people have been arrested in connection with the incident, three of which remain in police custody, the rest have been released pending further investigation.
Senior Investigating Officer, Detective Superintendent Jim Dunkerley, said: “Our investigation is continuing into the murder of Christopher Lewis.
“I am continuing to appeal for anyone who witnessed anything or has any information to come forward and assist with our enquiries.
“High visibility patrols are still continuing in and around the areas to provide support and reassurance to the local communities.”
Superintendent Joanne Morgan, of Leeds District Police, said: “I want to reassure our residents that we treat all firearms incidents extremely seriously and that they will not be tolerated in Leeds or West Yorkshire.
“We have now made a number of arrests in connection with this incident and are carrying out extensive investigations.
“Our neighbourhood policing teams are also very active and visible in the communities carrying out reassurance work and we are continually liaising with community partners to inform them of the situation and they have been incredibly supportive of our ongoing work.”
Anyone with any information to assist the Homicide and Major Enquiry Team with their enquiries is urged to contact the police via 101 or information can be passed to Crimestoppers anonymously on 0800 555 111.
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