In a letter to Leader of the Opposition and Sheikh Hasina, Rice said it would be an especially difficult time for the Awami League chief for her long association with Kibria.

"Please be assured that we're urging the Bangladesh government to apprehend and prosecute the perpetrators of these attacks," Rice was quoted by Saber Hossain Chowdhury as saying.

Secretary Rice said the failure to investigate these acts only foster "the climate of impunity further encouraging such attacks."

Rice hoped that the Bangladeshi qualities of resilience and fortitude would aid Sheikh Hasina and the people in pursuing justice for these crimes in a peaceful and lawful manner.