The stepson of British billionaire Hamish Harding defended going to a Blink-182 concert as rescuers search for his stepfather and other passengers on a missing sub. 

Brian Szasz stood by his decision on social media, writing that he is "not sorry" he went to see the band which has "helped me through hard times" while Harding and four other passengers on board OceanGate Expeditions' Titanic tourist submersible remain missing.

"Yes I went to @blink-182 last night," Szasz, a San Diego-based audio engineer, wrote in an Instagram Story on June 20, when he was pictured standing in front of a Blink-182 merchandise tent. "What am I supposed to do sit at home and watch the news?" 

"Not sorry this band has helped me through hard times since 1998," Szasz added.

SEARCH FOR MISSING TITANIC TOURIST SUB CONTINUES IN RACE AGAINST TIME

U.K. billionaire Hamish Harding receives a pin after traveling to space on a Blue Origin flight

Astronaut Hamish Harding receives his Blue Origin astronaut pin after a successful flight to space on June 4, 2022, in Van Horn, Texas. According to Action Aviation, a company for which Harding serves as chairman, the U.K. businessman was one of the mission specialists onboard a missing submersible carrying five people to view the wreckage of the Titanic that was reported overdue late Sunday, June 18, 2023. (Felix Kunze/Blue Origin via AP)

Szasz, 37, confirmed his stepfather was aboard the missing sub in a Facebook post Monday requesting thoughts and prayers for the rescue mission. Earlier, he wrote that it might be "distasteful" to go to the concert, but that "my family would want me to be at the blink-182 show as it's my favorite band and music helps me in difficult times," according to screenshots obtained by the Daily Mail and other outlets. 

He later deleted the post from the concert venue, writing that his mother requested he remove the post to protect the family's privacy. 

Blink-182 performs in New York City

From left to right, Travis Barker, Mark Hoppus and Tom DeLonge of Blink-182 perform onstage at Madison Square Garden on May 19, 2023 in New York City. Brian Szasz attended a Blink-182 show in San Diego on June 19, 2023, while his stepfather Hamish Harding and four others aboard a tourist submersible remain missing. (Manny Carabel/Getty Images)

On Twitter, Szasz thanked the members of Blink-182 for cheering him up through their performance. "My stepdad Hamish is on this submarine lost at sea. I’m devastated but coming to the San Diego show tonight so you guys can give me hope and cheer me up," Szasz tweeted. 

Fox News has reached out to Szasz for additional comment.

Harding is one of five passengers on an OceanGate Expedition tourist submersible that was reported missing Monday. The other passengers include Pakistani businessman Shahzada Dawood, 48, and his son Sulaiman Dawood, 19, as well as OceanGate CEO Stockton Rush and French mariner Paul-Henry Nargeolet. 

CANADIAN AIRCRAFT DETECTED ‘UNDERWATER NOISES’ FROM SEARCH AREA FOR MISSING TITANIC TOURIST SUBMARINE

OceanGate tourist submersible

An undated photo shows a tourist submersible belonging to OceanGate appearing on the water surface at sea. Search and rescue operations continue by the U.S. Coast Guard in Boston after a tourist submarine bound for the Titanic's wreckage site went missing off the southeastern coast of Canada. (Ocean Gate / Handout/Anadolu Agency via Getty Images)

U.S. and Canadian coast guard authorities have launched intense rescue missions in the days since the sub disappeared. The crew are sealed into the submersible, and it cannot be opened from the inside. The craft has enough stored oxygen to keep the crew alive for 96 hours.

There are now less than 24 hours of oxygen on board the missing OceanGate Titan submarine, according to an estimate from the U.S. Coast Guard.

The Coast Guard said Tuesday afternoon that there were just 40 hours left of "breathable air" inside the vessel.

By their estimate, it should run out by Thursday morning Eastern Standard Time.

MISSING SUB'S RESCUE UNLIKELY IN FRIGHTENING HUMAN DRAMA, SAY EXPERTS: ‘THE MATH IS NOT GREAT’

OceanGate tourist submersible

An undated photo shows a tourist submersible belonging to OceanGate as it descents at sea. Search and rescue operations continue by U.S. Coast Guard in Boston after a tourist submarine bound for the Titanic's wreckage site went missing off the southeastern coast of Canada. (Ocean Gate / Handout/Anadolu Agency via Getty Images)

Capt. Jamie Fredrick, U.S. Coast Guard First District response coordinator, told reporters in Boston that an ongoing search with the assistance of the Canadian Coast Guard in an area "larger than the state of Connecticut" has not yet turned up any signs of Titan. 

Fredrick said as soon as the Coast Guard received a report Sunday evening of the Titan’s disappearance, "we immediately launched search efforts."

"We flew assets that evening, and we've continued constant surface and air assets searches since that point," he added. 

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The 21-foot submersible, with five people on board, lost contact approximately 900 nautical miles East of Cape Cod, Massachusetts on Sunday, June 18. 

"Our thoughts and prayers are with the crew and the families and their loved ones," Fredrick said.  

Fox News' Sarah Rumpf-Whitten and Greg Norman contributed to this report.