A man who suffered an apparent heart attack in the panicked moments after Hawaii sent out a false warning of an imminent ballistic missile attack last year has filed a lawsuit against the state, claiming its gross negligence is responsible for his health condition.

James Sean Shields and his girlfriend Brenda Reichel filed the lawsuit on Tuesday in Hawaii state court.

The office of Hawaii governor David Ige referred questions about the lawsuit, and whether any other similar ones had been filed, to the state’s attorney general, Doug Chin, who did not respond immediately.

The lawsuit describes the harrowing moments after the all caps message, sent due to a mistake at the state’s emergency management agency, went out to cellphones on the island around 8 a.m. on Jan. 13, warning of a ballistic missile threat inbound,” and cautioning that, “this is not a drill.”

“Both plaintiffs believed this message to be true and were extremely frightened and thought they were shortly going to die,” the lawsuit states. “They decided that there was not much they could do to protect themselves from this threat and decided that if they were going to die, they might as well die together on the beach.”

Reichel’s son, a member of the Army National Guard in Hawaii, also told the couple that the threat was real. They made it to the beach around 8:15 a.m., and both called family members to tell them that they loved them, according to the complaint. Shields phoned his son and daughter on the mainland.

Shortly after the call, he began to feel a “severe and painful burning” in his chest, the complaint said. He tried cooling down in the ocean to no avail. So they headed to a nearby medical center, missing the 8:45 a.m. message sent to cellphones that said the warning was a false alarm.

Within minutes of arriving at the center, Shields had a heart attack, the complaint said. Shields underwent surgery at a nearby hospital, but the heart attack left him with heart damage, according to the complaint.

The complaint cites a statement from Dr. John MacGregor, a cardiologist at the University of California’s San Francisco Medical Center, who told the couple that the missile warning was a “substantial contributing factor in causing the heart attack and cardiac arrest.”

MacGregor said that Shields had no known cardiac disease before that time and noted literature with findings about how severe mental stress can trigger heart attacks. He cited a study in the medical journal Lancet that found a sharp rise in heart attacks when Iraq attacked Israel with missiles during the Gulf War, according to the complaint.

Shields’s account is just one of many to emerge about the moments after Hawaii sent the false missile alert. The incident was the result of a mistake during a training exercise at the Hawaii Emergency Management Agency; officials said that a worker, who later was fired, confused the drill for the real thing.

And for the nearly 40 minutes before officials corrected the warning with a follow-up text, hundreds of thousands of people on the archipelago state believed it was, too.