HARTFORD, Conn. -- Members of the State Police Major Crimes Squad are called in to help cities and towns across Connecticut solve homicides, arsons and robberies.

When someone walks inside of the major crimes van, it’s literally a lab on wheels with fingerprint dusters and DNA swabs all within reach.

The State Police Major Crimes Squad are the real life crime scene investigators. Those members of the squad have responded to over 150 crimes this past year – including high-profile cases like the killings of Yale graduate student Annie Le and UConn football star Jasper Howard. When the truck pulls up, detectives are ready to work.

Connecticut State Police Lt. Paul Vance said, “We cordon off the area. That’s why you’ll see yellow tape at a scene. We don't want people to come out; we don't want people to go in.”

The only people in and out of a scene are members of the squad. There are six or more detectives all assigned to a different part of the investigation.

To show the process of collecting evidence, members of the squad set up a fake crime.

One victim was shot in an apartment. The victim’s clothes, a weapon and bloody footprints are all part of what will become evidence is all left behind.

Step by step, they showed how the evidence will end up in the lab.

Blood plastered on the wall is enhanced by a solution and they mark everything that can be considered evidence.

The weapon, if left at the scene, gets special attention. The guns are unloaded at the scene and shell casings are packaged individually.

After hours of meticulous gathering, it’s off to the lab.

The first stop – test firing the gun.

The tests are required to see if the casings at the scene match.

The firearm can then be traced into a national database.

Anything that may have fingerprints on it is considered valuable as well as blood taken from the clothing.

Also, detectives now have technology to take a closer look into handwritten notes.

State police said it’s this kind of attention to details that has been instrumental in cases like the murder of Penney Serra who was killed in New Haven in 1973.

DNA evidence helped to convict her killer, Edward Grant, in 2002.

Currently, there are over 90 members of the state police major crimes squad who work every corner of the state to solve cases like Penny Serra.