British forensic scientists have developed a method that could be used to track fingerprints even after the print itself has been removed, the science news website of AlphaGalileo reported on Monday.

The method of taking fingerprints from a crime scene, developed by forensic scientists at the Forensic Research Center at the University of Leicester and the Northamptonshire Police's scientific support unit, enables scientists to "visualize fingerprints" even after the print itself has been removed, the report said.

The scientists conducted a study into the way fingerprints can corrode metal surfaces. The technique can enhance a fingerprint that has been deposited on a small calibre metal cartridge case before it is fired.

"For the first time we can get prints from people who handled a cartridge before it was fired. Wiping it down, washing it in hot soapy water makes no difference, and the heat of the shot helps the process we use," John Bond, Honorary Fellow at the University of Leicester and Scientific Support Manager at Northamptonshire Police was quoted as saying.

The procedure works by applying an electric charge to a metal ( a gun or bullet) which has been coated in a fine conducting powder, similar to that used in photocopiers, according to Bond who said " Even if the fingerprint has been washed off, it leaves a slight corrosion on the metal and this attracts the powder when the charge is applied, so showing up a residual fingerprint."

The technique the scientists described as "a major breakthrough in crime detection" works on everything from bullet casings to machine guns, and even if heat vaporizes normal clues, police will be able to prove who handled a particular gun, and it also works in cases where prints may be left on other metals, according to the scientists.

As a result of the research, cases dating back decades could be reopened because the underlying print never disappears, the scientists said.

Bond and his colleagues now intend to take this research forward to explore further the corrosion of metal by fingerprint residue and investigate how it might be used to detect more crime with forensic science.