Video footage of two British holidaymakers, including a Warwickshire tennis coach, hours before they were murdered has been released by detectives in Florida in the hope it will bring to light fresh evidence surrounding their shootings.
James Cooper, 25, from Warwick, and James Kouzaris, 24, from Northampton, were captured on a CCTV camera drinking and chatting to other customers in a downtown Sarasota bar, less than two hours before their dead bodies were found in a crime-riddled area of the Gulf coast city.
Officers from Sarasota Police Department are also following up a number of leads gleaned from photographs which were recovered from one of the dead men's cameras.
The 11 CCTV stills, which were taken in Smokin' Joes bar and cover a time period from 12.13am to 1.23am, clearly show the university friends talking to two women for at least 37 minutes.
Police stressed the revellers were not suspects, but said they wanted to contact them to "learn more details about the victims' activities", and see if they may have been in contact with other people before they were murdered on Saturday April 16.
Mr Kouzaris, wearing a grey crew-neck T-shirt, and Mr Cooper, dressed in a black V-neck T-shirt, stand directly in front of a camera in the bar in conversation with the two women.
The four are together in the footage from 12.13am and appear to go out of shot together at 12.50am. The next still is from 1.02am and their place has been taken by two other women.
The two Britons reappear at 1.21am towards the middle of the bar, with their backs to the camera and talking to a blonde woman. In the final still two minutes later, they are still talking to her.
Ninety minutes later they were lying dead in a rundown street 20 blocks away.
It is still unclear what the former Sheffield University students were doing in the Newtown housing project locals routinely described as very dangerous.
The murder scene - about 12 miles from the upmarket island city of Longboat Key where the friends were staying - is reportedly rife with drug dealing and prostitution.
Captain Paul Sutton said detectives were "examining all theories" and "keeping an open mind" as to how and why the duo ended up in the "no-go" area.
Shawn Tyson, 16, who lives close to the murder scene, is being held on suspicion of double murder. Police said the teenager would be charged as an adult over the two murders, which means he could face the death penalty if convicted.