Investigators Determine Gas Leak Caused Explosion That Killed NFL Player's Father

Robert Farley died in an explosion at his son Caleb's mansion in North Carolina.
The explosion was caused by a natural gas leak according to investigators.
The mansion was completely destroyed and another person was injured.
Caleb Farley, who plays for the Tennessee Titans, was not home during the explosion.
Farley's teammates and coach expressed support after his father was honored at a memorial service.