Terror police are to review the evidence into the IRA bombing of Manchester, 20 years on from the outrage.
Detectives will reopen files and asses the evidence again to see if further investigations can be carried out to catch the perpetrators.
No one has ever been charged over the bombing, which left 200 injured.
The 3,000lb device was detonated near the Arndale Centre on June 15 1996, causing widespread devastation across the city centre.
Miraculously, no one was killed.
Detective Chief Superintendent Tony Mole, head of the North West Counter Terrorism Unit, said: "The Manchester bomb affected many people which is why the case has remained open and has been kept under constant review.
"As part of this process a team of specialist officers carried out a more detailed review ahead of the 10th anniversary of the incident.
"In 2006 in consultation with the Crown Prosecution Service, we concluded at the time there was no realistic possibility of prosecution.
"As the 20th anniversary of the incident approaches, it is now the right time for another assessment of the case in order to identify and explore any possible potential investigative opportunities.
"If new information comes to light it would be considered and I would urge anyone with information relevant to the investigation to get in touch with police."
Tony Lloyd, interim mayor and the Police and Crime Commissioner for Greater Manchester, said: "I fully support Greater Manchester Police in carrying out a further assessment and update to see if it is possible to bring the perpetrators of the Manchester bombing to justice.
"I also further call on the Home Secretary to make resources available to allow for a thorough review of the case to be undertaken, so that the people of Greater Manchester can be reassured that everything is being done to identify and prosecute the perpetrators.
"The events of 20 years ago brought devastation and fear to the streets of Manchester.
"While the city has risen to be stronger than ever, that day has had a long-term impact on those caught up in the blast. They, and the communities of Greater Manchester, deserve to know that no stone has been left unturned."
Anyone with information should contact police on 101, or the independent charity, Crimestoppers, anonymously, on 0800 555 111.