A seven-year-old boy has died after being buried alive by his younger brother as they played in a pile of sand at their rural home.

Wyatt McDaniel was pulled unconscious from the mound of sand after his five-year-old brother alerted their father.

Despite desperate efforts by Charlie McDaniel to revive his son with CPR and later by paramedics the boy went into cardiac arrest.

McDaniel was pronounced dead after being airlifted by helicopter from the family's horse farm in Bexar County, Texas.

Police said it appeared the two boys had been playing in a pile of loose beach sand at the horse farm and riding school.

It is believed they had dug a hole in the top the pile of loose sand and younger brother Logan may have piled the sand back on top trapping his brother.