Yesterday a spokesman from the centre confirmed the photograph of the couple on the beach had been removed from its Facebook page.
"The number of messages received via email from foreign persons from New Zealand and other countries ... have asked the management [of this] page to delete a [photo of] corpses that were found on the shore of the city of Sabratha because [of] their parents," he said. "We have deleted [at] the request of many of our viewers."
Mfat yesterday dismissed reports from Libya that four people had been arrested in connection with the murders.
"We have been advised by the Libyan authorities that no arrests have been made," said spokesman Adham Crichton. "An investigation by the Libyan authorities into Ms Howie's death is under way."
The motive for the killing is not known. It may have been political, or the result of an adverse reaction to the presence of an unmarried couple by extremist Muslims.
The area where they were found is said to be extremely remote and accessible only by 4WD. Beachgoers have been targeted by armed thieves there in the past, though there is nothing to suggest the couple were killed in a botched robbery.
Expat Di Alpers said there was a lot of speculation about why the couple were killed. "The most consistent is that [they] were in the wrong place at the wrong time and may have witnessed something untoward such as gun running, or loading of boat people, or black market deals."
Ms Howie's family have declined to comment on her death, as has Mr De Salis' Blenheim-based brother Roger. His cousin Richard De Salis offered his condolences and best wishes to Ms Howie's family.