Andrew Garcia, 23, Victoria Dempsey, 20, Kelsie Karpiak, 24, and Jason Soleimani, 23, killed and Kathy Payne, 24, injured in boat crash in Miami on July 4.

The fireworks in Miami had just concluded when a white, 32-foot (9.6-meter) boat carrying five young adults crashed violently with another vessel in the night.

The boat's operator was thrown overboard. Another passenger was tossed into the water, and two others left critically injured and unconscious.

With no one at the helm, the boat circled in the dark, crashing into a third vessel before a commercial salvage crew was able to pull up alongside it, jump aboard and bring it to a stop.

When the waters calmed again, rescuers struggled through the dark to piece together a devastating toll: Four dead, eight injured.

That was the account investigators detailed Sunday, two days after the deadly Fourth of July crash.

"I can tell you, based on the officers on scene, it was one of the most chaotic scenes that they have ever been involved in," said Jorge Pino, a spokesman for the Florida Fish and Wildlife Conservation Commission.

Authorities identified the victims as: 23-year-old Andrew Garcia, 20-year-old Victoria Dempsey, and 24-year-old Kelsie Karpiak, all from Miami and on the first boat. Jason Soleimani, 23, of Old Westbury, New York, was on the second vessel and killed immediately.

The crash happened at about 10:45 p.m. Friday, as hundreds of boats were in the waters of Biscayne Bay, admiring the fireworks along Miami's gleaming skyline.

Pino said the minute the fireworks conclude boaters typically rush toward Dinner Key Marina, hoping to get their boat out of the water first.

"So you have hundreds of vessels moving at one time, in the dark, which is a recipe for disaster," he said.

It's still unknown what speeds the boats were travelling at, but investigators say the second vessel was hit with such force that a hole was left in its side. Eight people were on board the 36-foot-long fiberglass vessel, including a 2-year-old girl. In addition to Soleimani, six people were injured and hospitalized, one in critical condition.

The toddler and another child were not injured.

Meanwhile, the first vessel continued on, its captain thrown in the water, striking a 35-foot (10.5-meter) Boston Whaler with nine people on board. Only one sustained minor injuries.

Capt. Burt Korpela of Atlantis Marine Towing and Salvage was one of the first on the scene, responding to a distress call.

He encountered a horrific sight: The first boat, still spinning out of control.

"The boat was running out of control in circles 20 to 25 miles per hour (32 to 40 kilometres per hour), limited lights on the boat," Korpela told CBS4. "You've got to jump from one boat to another. It's just the most extreme you can do and this accident was terrible."

One of the women found unconscious on the boat, Karpiak, was pronounced dead after being taken to the hospital. Another, 24-year-old Kathy Payne, was in critical condition.

Garcia — believed to be the operator of the first boat — and Dempsey, both thrown overboard, were found dead on Saturday.

Pino said no charges have been filed, though the investigation remains ongoing.