Strathclyde University student Suleman Dawood felt "terrified" before embarking on a trip to the Titanic shipwreck - with his dad Shahzada and three others - his aunt has revealed.
The 19-year-old was on the Titan submersible when it went into the ocean off the coast of Newfoundland, in Canada, on Sunday, and never returned.
Others on board included his dad Shahzada, 48, Stockton Rush, the chief executive and founder of OceanGate Expeditions, Paul-Henri Nargeolet and billionaire pilot Hamish Harding.
The US Coastguard yesterday announced (June 22) that the five men are believed to have died in an implosion after a debris field was discovered in the search for the missing submarine.
READ MORE: Heartbroken family pay tribute to Glasgow student who died on lost Titanic sub
His aunt, Azmeh Dawood, told NBC news that she found it "difficult to breathe" when thinking of her loved-ones trapped on the vessel.
She said her nephew Suleman "wasn't very up for it" and felt "terrified" about the trip to explore the wreckage of the Titanic.
Following the tragic update on Thursday evening, tributes have been pouring in for the Glasgow student and his dad - the Pakistani nationals who lived in London.
The Dawood Foundation, of which Shahzada was a trustee, wrote: "With heavy hearts and great sadness, we grieve the loss of our trustee, Shahzada Dawood, and his beloved son, Suleman Dawood.
"Our thoughts and prayers are with the Dawood family at this tragic time."
Shahzada supported the British Asian Trust, who said they are "deeply saddened" by the tragedy.
A spokesperson said: "Shahzada was a wonderful and generous man who supported our work in South Asia for many years, while his son was just emerging into adulthood with a promising future ahead.
"Our hearts and prayers are with family and friends at this unimaginable time of grief and loss. Our deepest condolences to them and everyone else who lost loved ones in this terrible incident."
The Pakistan Foreign Ministry said: “Our deepest condolences to the Dawood family and the family of other passengers on the sad news about the fate of Titanic submersible in the North Atlantic. We appreciate the multinational efforts over the last several days in search of the vessel."