ST. JOSEPH, Mo. — The second defendant charged in connection with the death of a Northwest Missouri State University student last September has pleaded guilty. Tony Overlin, 24, Bethany, entered the plea Wednesday in Buchanan County Circuit Court to first-degree involuntary manslaughter in the death of 21-year-old Tomarken Smith. Under a plea agreement, Overlin was sentenced to six years in prison. Smith, from suburban St. Louis, died last September after an altercation outside Molly's Dance Club & Bar in Maryville. He was a senior majoring in pre-professional studies and minoring in coaching. On Tuesday, 32-year-old Kevin Mooney of Bethany also pleaded guilty to first-degree involuntary manslaughter. He will be sentenced Sept. 30. Presiding 4th District Circuit Judge Roger Prokes accepted Mooney's guilty plea and ordered the Missouri Board of Probation and Parole to prepare a sentencing assessment report. Both men were originally charged with second-degree murder and first-degree assault in connection with Smith's death. On Sept. 14, 2012, following an altercation inside the bar, Overlin and Mooney attacked Smith, punching him in the head as he walked down the sidewalk with a friend. The blows caused Smith to fall and hit the back of head on the sidewalk near the intersection of Fourth and Market streets on the downtown square. Though officers reached Smith within seconds of the attack and began administering CPR, the young man never regained consciousness and died less than an hour later in the St. Francis Hospital emergency room. Overlin was sentenced to one year less than the maximum term of incarceration for a Class C felony. Judge Patrick Robb ordered the sentence executed, and Overlin was taken into the custody of the Buchanan County Sheriff's Department pending processing by the state Department of Corrections. Rice said Smith's family and police were consulted as he negotiated with Overlin's attorneys with regard to the plea bargain. "Both law enforcement and Tomarken's family were involved from the very beginning, and agreed that the final outcome of this case was just and appropriate," said Rice, adding that members of Smith's family were present when the sentence was handed down. The Associated Press contributed to this story.