Advances in DNA testing have made it easier for police to track down criminals and have led directly to a number of arrests in Hertsmere in recent months.

A thief who raided a Borehamwood pharmacy stealing around £2,500 worth of goods, was jailed for 14 days earlier this year after Hertfordshire Police traced him through a drop of blood left at the crime scene.

Police believe that Allen Buckley, 36, of no fixed address, cut himself after smashing a window to enter Shenley Pharmacy in Shenley Road on January 1.

Buckley, who had previous convictions, was traced because police were able to match the blood to DNA samples taken after an earlier arrest.

Another serial offender, who has carried out 40 crimes across Hertfordshire, including Radlett, Elstree and Borehamwood, was recently arrested after police found some blood where he had cut himself during a burglary.

Police can now do more than just tracing someone from blood and fingerprints.

Criminals can be jailed after leaving hair, skin cells, sweat or even saliva on a cigarette butt at a crime scene.

Following a recent burglary in Radlett, Jason Bovell was convicted after beads of sweat, left on the outside of the window where he gained entry, were found and tested positive.

Another man was convicted of a burglary in Shenley after police identified the DNA on dead skin cells found inside a glove he was wearing to stop himself leaving fingerprints.

Detective Sergeant Neil Langford from the priority crimes unit in Hertsmere, said: "People try to disguise themselves and just don't think of every angle.

"Wherever you go, you will always leave a trace of something — it just shows how you can catch people nowadays.

"With such advanced methods of forensic science, the possibilities are endless and the message for criminals is that there really is no where to hide."