Khalil Dale's brother Ian, his friends Zia and Dora and fiancee Anne expressed their sadness with this statement:
"We are shocked and saddened beyond comprehension for the senseless and brutal way in which our beloved Khalil was murdered.
"At this painful time we feel many mixed emotions, including hurt, grief, confusion and anger. We particularly need time and space to grieve our loss, and do respectfully ask that the media respect this.
"During Khalil's abduction and following his death, there has been an overwhelming flood of support, kindness and love from all corners of the globe, and we are very humbled and grateful for this empathy and solidarity.
"In particular, we wish to thank the Red Cross and Red Crescent family across the world for their support and for their focus throughout on Khalil's safe release. We have been with them throughout this ordeal, and we know they share our grief.
"We do not wish to see the inhumanity and brutality of his death debase the memories we have of Khalil. Without question, Khalil was amongst the most gentle, most kind and most loving person we have ever known.
"For all who knew him, his deeply caring and considerate nature was what left a lasting impression.
"His tireless work with the most impoverished and vulnerable people of the world was a reflection of his beliefs in love, in solidarity and in compassion. He was a true humanitarian.
"We will not let the events of the past week sully Khalil's memory. Khalil was a better man than that. We pity those who took his life.
"He achieved much in this world. His life was one of love, not hatred. His life was one of kindness, not cruelty. His life was one of beauty and joy.
"We will always remember our Khalil, our Ken, as a man who brought joy to us and countless others."
More top news
A B&B and holiday cottages in Stranraer have received 4-star ratings from Visit Scotland. Owners hope this will boost tourism to the area.
A Carlisle woman who tried to steal her own £21 takeaway meal has been landed with a £310 court bill.
The Billy Bland Challenge was set up in 2010 for any team to try to beat his 35-year record. Over the weekend, new runner-up times were set.