Police in Northampton are trying to track down 28 key people who may have witnessed the death of two girls who were crushed in a nightclub a year ago.
Around 1500 students from universities all over the country attended the Wickedest Wickedest club night at Lava & Ignite nightclub and many travelled to Northampton in organised coaches.
Some of the students came from Kent and Portsmouth.
Police have stressed that they do not suspect the people in the photo or the CCTV coverage of any criminal offence
Officers have also set up dedicated Facebook and Twitter accounts for this appeal at: