London police have charged two correctional officers and a supervisor in connection with the death of an inmate at the Elgin-Middlesex Detention Centre.

Police officials say a second investigation into the death of Adam Kargus was prompted by interviews with staff and inmates, and a review of surveillance video that were part of the initial investigation.

A statement released by investigators says “Information obtained during this investigation determined that a second investigation was required to look into the actions, or lack thereof, of correctional staff leading up to and during the homicide. ”

As a result of the second investigation, 47-year-old Leslie Lonsbary, 55-year-old Gregory Langford, and 52-year-old Stephen Jurkus, an operational manager, are charged with failing to provide the necessaries of life.

The three accused will appear in a London court on April 15.

Adam was beaten to death in his holding cell on Oct. 31, 2013. His body was found the next morning in the communal showers.

His cellmate, Anthony George, has been charged with second-degree murder and two other men have been charged with being an accessory after the fact.

London police say this is the first time they've laid these types of charges against correctional officers.

Det.-Insp. Kevin Heslop explains "The correction officers had an obligation, in law, to protect this inmate - Mr. Kargus - and every inmate from potential harm, and in our view they didn't meet that threshold and as a result they are being charged."

Correctional officers are expected to check on inmates every 30 minutes overnight, but there are allegations this wasn't done as Kargus' cries for help and those of other inmates went unheard.

Lawyer Kevin Egan says "These guards could not possibly have been doing their duty when Adam was killed in the way that he was."

He adds "A number of witnesses have indicated to me that the guards knew or ought to have known that Anthony George had been drinking that day...and that they then locked Adam in a cell with someone who they knew or ought to have known was drunk and prone to violence."

Andrew Morrison, a media relations representative with Ontario's Ministry of Community Safety and Correctional Services, responded to CTV News inquiries with an email that reads:

"It would be inappropriate to comment on the specific charges involving staff at the Elgin Middlesex Detention Centre given the ongoing legal proceedings. I can confirm that staff in this matter will be suspended pending the outcome of the ministry’s internal investigation."

But Warren 'Smokey' Thomas, OPSEU president, says "From the beginning, the ministry resisted making changes. Now, lives have been lost and the very people who raised the concerns are being criminally charged. This is heart-breaking on all levels."

Adam's older brother Shane Kargus remains angry, "It's hard to be happy, but it's nice to see...There really needs to be a change in the morals in the people who are responsible for so many lives inside these facilities."

Still he says he will never have closure, and his brother's death "will live with me forever."

Political reaction at Queen's Park

A number of local MPPs spoke out on the issue of violence at EMDC at the legislature on Wednesday.

Elgin-Middlesex-London MPP Jeff Yurek says "Since I've been elected in 2011, I've had people in my office both on the union side and on the management side, saying, look it, we're overcrowded here.

"There's potential for great danger here for not only the guards but also the inmates at the detention centre. We need something to be done. I've been pushing this minister, since the day I was elected, that she need to put a focus on the EMDC and she's failing to do so."

London West MPP Peggy Sattler pushed for reaction from the Liberal government saying "Why is this government failing the inmates, their families and the correctional officers at EMDC by not addressing the under-staffing, overcrowding and design flaws at the facility?"

Madeleine Meilleur, the minister of correctional services, responded "Despite best efforts, Mr. Speaker violence is a reality for correctional facilities everywhere. On a daily basis correctional staff deal with and manage risk of inmate violence."