Two people have been arrested on suspicion of causing death by dangerous driving after a mother and daughter were killed crossing the road in Strood.
Police arrested a 21-year-old man and a 19-year-old woman, both from Chatham, on Thursday.
The man is the driver of a Ford Fiesta which was in the area at the time. Both have been bailed pending further investigation.
The driver of a silver Seat Ibiza, which hit the couple in Station Road, has not been arrested.
On Sunday, a week after the crash - which killed Elsie Blades, 84, and her 60-year-old daughter Marilyn Herlihy - more than 400 vehicles were stopped and motorists questioned by police at the scene in a bid to find witnesses.
Elsie was pronounced dead at the scene. Marilyn was airlifted to the Royal London Hospital by Kent Air Ambulance, but died later.
Anyone with information is urged to contact police on 01622 798535 or Kent Crimestoppers on 0800 555111.
Don't miss out, subscribe today. Keep up to date with our newsletters.
A guide for your future. For year 11 students in Kent and Medway. Click here for the e-edition.
Education, Training & Childcare is a special supplement published by KM Media Group four times a year. Click here for latest e-edition.
Get the latest food and drink news, recipes from some of the nation's top chefs plus updates from Kent's vineyards and breweries.
Search in your local area to find your perfect partner in Kent, with FreshStart Dating! PLUS, register for free!.
Find out what's going on in the garden, with Kent expert Lucy Hewett's weekly update.
Buy pictures that you've seen in a KM newspaper, or send in a picture and we will place it on our photo sales website so that you can purchase a super, unique gift.