Greek police have brought five people in for questioning in the case of murdered UC Berkeley professor Przemyslaw Jeziorski, who was shot dead on July 4 while visiting Athens to see his children and attend a family custody hearing.

Our family is heartbroken, and we are doing everything we can to ensure that justice is served,” his grieving brother said.

Greek authorities arrested the ex-wife of a UC Berkeley professor in connection with his murder in Athens earlier this month. Marketing professor Przemyslaw Jeziorski was fatally shot July 4 in the Agia Paraskevi district of Athens, authorities told Greek media outlet To Vima.