A Dutch international volleyball player whose dismembered body was found buried along with that of her partner in rural Spain may have been pregnant when she was tortured to death, according to reports in local media.

The remains of former Olympian Ingrid Visser, 35, and her boyfriend Lodewijk Severein, 57, were found buried in a lemon grove on Sunday following a business deal that is reported to have gone wrong in the city of Murcia, in the south-east of Spain.

One of three men arrested over the couple's alleged murders is 36-year-old Spaniard Juan Cuenca Lorente, former athletic director of the CAV Murcia volleyball team, for which Visser played from 2010 to 2012, according to Spanish newspaper La Verdad.

The other two men have been identified as Romanian nationals Ion Valentin, 59, and Constantin Stan, 47. They allegedly were hired as hit men in the murder plot.