Talal al-Massouri told ITV Wales three members of his family are still missing and 25 have died.
A father in Newport has spoken of his devastation after losing 25 members of his family in floods in Libya.
Talal al-Massouri says three of his relatives are still missing.
"We just lost cousins there, yesterday one of my cousins, her husband and four kids just died.
"It's really hard, you can't explain it. No-one can explain it. It's just too much".
So far more than 11,000 people are known to have died in the tragedy - but that figure is expected to rise.
Mr al-Massouri shared videos of the aftermath of the disaster which he had been sent by his sister, who is still in Libya.
He told ITV Wales: "All these houses see all these blocks of houses, they've all washed away - and both sides. So can you imagine how far they went and to reach this mosque and destroy all these houses." "Derna was one of the cities affected by the storm and, for us, it was really shocking. We did worry about our family who are there because we lost contact with them.
"This is what worried everyone, not only my family but everyone I know who is from my city and lives in the UK."
Survivors, left homeless on the flood-ravaged streets of Libya, are desperately awaiting aid, as pressure grows on the country's divided rival governments to unite in the face of tragedy.
In the five days since the devastating deluge hit the north African country, 11,300 people have died, whole families and villages have been wiped out and thousands remain missing.
While many towns and cities in eastern Libya saw deadly flooding, Derna was the worst-hit.
Derna had no evacuation plans, and many residents said they did not know they were in danger until they heard the explosive sound of two dams rupturing.
But this tragic disaster could have been avoided, according to a top UN official.
“If there would have been a normal operating meteorological service, they could have issued the warnings," World Meteorological Organization head Petteri Taalas told reporters in Geneva.
"The emergency management authorities would have been able to carry out the evacuation.”
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know…