NEW ORLEANS — The Coast Guard on Saturday evening called off its search for two workers missing after a fire broke out on an oil platform in the Gulf of Mexico, sending an ominous black plume of smoke into the air reminiscent of the 2010 Deepwater Horizon explosion that transformed the oil industry and life along the U.S. Gulf Coast.

Chief Petty Officer Bobby Nash said the search was ended at about 5:25 p.m.

Helicopters had been searching for the missing workers from the air, while a cutter searched the sea.

The blaze erupted Friday as workers were using a torch to cut an oil line on a platform owned by Houston-based Black Elk Energy about 20 miles southeast of Grand Isle.

Four workers were severely burned, though Black Elk Energy spokeswoman Leslie Hoffman said their burns were not as extensive as initially feared.

Officials at Baton Rouge General Medical Center said Saturday that two men remained in critical condition, while two men remained in serious condition. All four, who are being treated in a burn unit, are employees of oilfield contractor Grand Isle Shipyard and are from the Philippines.

The hospital said it and Grand Isle Shipyard are trying to reach the men’s families in the Philippines.

It’s unclear whether the missing men worked for a contractor. Grand Isle Shipyard employed 14 of the 22 workers on the platform at the time of the incident. A man who answered the phone at the company’s Galliano office on Saturday said no one was available to comment.

Meanwhile, officials said no oil was leaking from the charred platform, a relief for Gulf Coast residents still weary two years after the BP oil disaster illustrated the risk that offshore drilling poses to the region’s ecosystem and economy.There were a few important differences between this latest blaze and the blaze that touched off the worst offshore leak in U.S. history: Friday’s fire was put out within hours, while the Deepwater Horizon burned for more than a day, collapsed and sank.

The site of Friday’s blaze is a production platform in shallow water, rather than an exploratory drilling rig looking for new oil on the seafloor almost a mile deep.

The depth of the 2010 well blowout — a mile below the surface — proved to be a major challenge in bringing the disaster under control.

The Black Elk platform is in 56 feet of water — a depth much easier for engineers to manage if a spill had happened.

A sheen of oil about a half-mile long and 200 yards wide was reported on the Gulf surface, but officials believe it came from residual oil on the platform.

“It’s not going to be an uncontrolled discharge from everything we’re getting right now,” said Coast Guard Capt. Ed Cubanski.

Hoffman, the Black Elk Energy spokeswoman, said Saturday that there were still no signs of any leak or spill at the platform site.

BP’s blown-out well spewed millions of gallons of oil into the sea, about 50 miles southeast of the mouth of the Mississippi River on the east side of the river delta. The crude fouled beaches, marshes and rich seafood grounds.

After Friday’s blaze, 11 people were taken by helicopter to area hospitals or for treatment on shore by emergency medical workers.

The production platform is on the western side of the Mississippi River delta.

“The company continues to cooperate closely with all state and federal agencies,” company officials said in a news release Saturday. “As reported yesterday, this platform was not in operation and had been shut in since mid-August. According to visual reports from this morning, there is no visible sheen in the vicinity of the platform.”

Cubanski said the platform appeared to be structurally sound. He said only about 28 gallons of oil were in the broken line on the platform.

Associated Press writer Kevin McGill in New Orleans contributed to this story.