It happened early Monday morning at an east Amarillo night club.
The man was found dead in the parking lot of the Las Chakalozas club on the 1500 block of east 10th just after closing time.
Because the investigation is in its early stages, police are releasing very little information.
What we do know at this point is Lamberto Sifuentes is dead and no suspects have been identified.
Police arrived at the club just after 2 a.m. where they found Sifuentes lying on the ground.
Another man, presumably his son, was performing CPR but he was declared dead when paramedics arrived.
Police say they're getting conflicting reports as to whether there was an altercation inside the bar prior to Sifuentes' death
Special Crimes Unit Lt. Erick Bohannon says they received two 911 calls from the bar.
Sifuentes' son was also injured. He's hospitalized with non life threatening injuries.
Police are not releasing the name of the second victim. He tells police they were both assaulted with some type of weapon.
This is the third time in two weeks the Special Crimes Unit has been called in to investigate a death.
Though last night's death of sifuentes and last week's shooting death of Matthew Guzman, 22, have not yet been classified as