EVERETT — OceanGate, the Everett-based company that owned and operated the deep-sea submersible that imploded last month and killed all five people aboard, including the firm’s CEO, has suspended operations, according to the company’s website.

The announcement appeared Thursday in red letters stripped across the OceanGate Expeditions website.

“OceanGate has suspended all exploration and commercial operations,” the banner read.

Questioned Thursday about any plans to layoff employees or vacate its headquarters at the Port of Everett, an OceanGate spokesperson told The Daily Herald in an email, “OceanGate can’t offer any details beyond the statement on its website at this time.”

The sub, known as Titan, was exploring the wreck of the Titanic at a depth of 12,500 feet in the North Atlantic when it lost contact with the mothership June 18. It is believed to have imploded that same day.

The implosion killed all five people on board, including Stockton Rush, the company’s chief executive, who was piloting the vessel.

The other victims were Pakistani businessman Shahzada Dawood and his 19-year-old son, Suleman; Hamish Harding, a British explorer, and French diver Paul-Henri Nargeolet.

OceanGate charged passengers, dubbed “mission specialists,” $250,000 for the 10-hour trip to descend and view the wreck of the Titanic.

At least 46 people successfully reached the wreck of the Titanic on the sub in 2021 and 2022, according to company letters filed with a federal court that oversees matters related to the 1912 sinking of the ocean liner.

Rush founded OceanGate in 2009 and moved operations from Seattle to the Port of Everett in 2015 for the water access and space. OceanGate shares its street address with Scuttlebutt Family Pub and the Port’s Waterfront Center.

At the port this week, security officials weren’t allowing visitors into the parking lot or boatyard operations near OceanGate’s headquarters. Only boat owners and boatyard workers were being given access to the area.

Port CEO Lisa Lefeber said the step was taken for security reasons. “Too many people are trying to access the yard to view their space, which compromises other businesses’ security,” Lefeber said in an email Thursday to The Daily Herald.

OceanGate’s lease at the port is up July 31, 2025, Lefeber said.

For a week in December 2021, the a 21-foot capsule was displayed in front of the marina.

OceanGate is based in Everett. OceanGate Expeditions, a separate but related company that led the Titan’s dives to the Titanic, is registered in the Bahamas.

Forbes reported June 23 that OceanGate’s board of directors would be “considering the company’s survival.”

The Coast Guard is investigating the implosion.

The sub’s wreckage was found on the seabed about 1,600 feet from the wreck of the Titanic, the U.S. Coast Guard said.

The Titan submersible “was not a U.S. flagged vessel and was never certified or certificated by by the U.S. Coast Guard,” the Coast Guard said.

In 2018, the company drew the attention and scrutiny of the Marine Technology Society, an international trade group that promotes the advancement of marine technology. The group sent a letter to OceanGate expressing concern that the company had ignored industry-wide safety standards.

That same year, a former OceanGate Expeditions employee, hired to ensure the safety of submersibles and their passengers and crew, claimed OceanGate ignored warnings that the carbon-fiber sub was potentially unsafe, according to a 2018 lawsuit filed in federal court.

The former employee alleged the vessel’s carbon fiber hull could be weakened by the constant pressure exerted at extreme depths, resulting in large tears in the carbon.

Titan was built with a carbon fiber and titanium hull, a one-of-a-kind material combination. Other deep-sea small submersibles are typically built from steel and titanium, experts have said.

OceanGate claimed in promotional materials and videos that the University of Washington, The Boeing Co. and NASA participated in the sub’s design and construction. All three entities denied involvement.

Janice Podsada: 425-339-3097; jpodsada@heraldnet.com; Twitter: @JanicePods.

Information from the Associated Press is included in this report.