The Seay brothers -- Cortez, left, Martez and Demarius -- were church-going, often-disciplined boys growing up, their family says. Currently, one brother has been convicted of and the others ...

Police said that on May 3, 2009, Martez Seay gunned down Lonnie Vaughn in Center Point with help from his girlfriend Kandi Hawkins. Evidence in that case linked Seay to four other murders.

Martez Seay, 39, was found unresponsive in his cell at the Limestone Correctional Facility on Monday, August 7, according to the Alabama Department of Corrections (ADOC).

Police arrested Martez Seay, 25, around 6 p.m. Tuesday at an apartment on Tuscaloosa Avenue in west Birmingham.Vaughn was found May 3 by a man who was walking his dog.

Martez Seay pleaded guilty Thursday to capital murder in the deaths of five people in the Birmingham area in 2008 and 2009. Prosecutors agreed to seek sentences of life without parole.

Police said that on May 3, 2009, Martez Seay gunned down Lonnie Vaughn in Center Point with help from his girlfriend Kandi Hawkins. Evidence in that case linked Seay to four other murders.