Nashville police have now identified four persons of interest in regards to the fatal stabbing incident that killed singer-songwriter Tucker Beathard's brother, Clayton, early Saturday morning (Dec. 21).

The people, pictured above, are wanted for questioning in regards to the incident. Police are asking for the public's help in identifying the three men and one woman. Anyone knowing the identities of these persons is asked to contact Nashville Crime Stoppers at 615-742-7463.

Police initially released footage showing just one man thought to be involved in the incident, seen below.

According to Nashville's NewsChannel5, police responded to a call at the Dogwood Bar on the 1900 block of Division Street shortly before 3AM on Saturday after three men were stabbed over an argument involving a woman.

Police say the argument began inside the bar and escalated into physical violence after it spilled over into the outside. Beathard, 22, and Paul Trapeni III, 21, were transported to Vanderbilt University Medical Center, where both men subsequently died. A third victim was released after receiving medical treatment.

Clayton Beathard was a high school football star who went on to play for Long Island University. Brother Tucker is not the only musician in the family: Their father is Nashville songwriter Casey Beathard, who has written for artists including Gary Allen, Kenny Chesney, Eric Church and more.

The Beathard family is additionally well-represented in sports, with Clayton having had an impressive football pedigree. His other brother, C.J. Beathard, is a quarterback for the San Francisco 49ers. Their grandfather is NFL Hall of Famer Bobby Beathard, who won four Super Bowls as a general manager.

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