In an article published in the December 16 edition of "The Washington Post," Anadurdy Khajiev urges the U.S. Embassy in Ashgabat to release post-mortem photographs of Muradova, which he says are evidence that the 58-year-old woman was tortured to death.
Turkmen authorities reportedly authorized U.S. Embassy officials to photograph Muradova's body at the Ashgabat city morgue.
Muradova's relatives say the body had a deep head wound and marks of strangulation.
In addition, Anadurdy Khajiev says one of Muradova's legs was broken and that her arms and legs "were punctured where injections [of psychotropic drugs] had been administered."
On August 25, Muradova was sentenced to six years in jail on charges of illegally possessing ammunitions.
Sapardurdy Khajiev and another of Muradova's co-defendants – Annakurban Amanklychev – received seven years each on similar charges.
Rights groups have criticized their trial as a parody of justice based on trumped-up charges.
Anadurdy Khajiev says his brother's whereabouts and those of Amanklychev remain unknown.
He also says relatives of all three defendants have been fired from their jobs and threatened with imprisonment if they gave any information to western media or rights groups.