CCTV footage from the area where Eliza and Henrietta were last seen is being examined by Police Scotland.
They were last seen crossing the Victoria Bridge and turning right onto a footpath next to the River Dee, heading in the direction of Aberdeen Boat Club.
Searches on Monday explored an area between Wellington Bridge and the South Harbour.
Ch Insp Darren Bruce said the river remained the focus of the search and there was “no evidence” of the sisters leaving the area.
He urged anyone who may have seen them or who has private CCTV or dashcam footage from the area to come forward and share information with officers as soon as possible.
He said: “Eliza and Henrietta’s family remain extremely worried about them and we are in regular contact with them as our searches continue.
“We know that people across Aberdeen are also seriously concerned for the two missing sisters and I would again urge anyone with information which could help to get in touch with us.
“Extensive efforts remain ongoing in the area, with specialist officers continuing to search on the banks of the river, while door-to-door inquiries are also continuing at homes and businesses in the surrounding area.”
Ch Insp Bruce added: “Even if it doesn’t seem significant, please pass any information on. Any piece of information could prove crucial.”
