3 dead in 21-vehicle pileup on I-75 in North Florida on New Year's Day; dense fog could be to blame

LAKE CITY, Fla. - Troopers are investigating a 21-vehicle chain-reaction crash that killed three people on Interstate 75 in North Florida, which happened just after midnight on New Year's Day.

The Florida Highway Patrol said the deadly multi-vehicle collision happened in the northbound lanes near mile marker 414, in Lake City.

The crash involved "in excess of forty-five persons, three of whom were killed," FHP said. According to troopers, the three victims — two men and one woman — were from Chicago. Their identities were not released.

(Courtesy: Florida Highway Patrol)

Five separate rescue units transported injured drivers and passengers to Lake City Medical Center or to Shands Hospital at the University of Florida, according to FHP. However, investigators said they have not yet determined the exact number of people who were injured because some drove themselves to medical facilities.

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It took 12 hours for the major crash investigation unit to finish mapping the scene, collect evidence and remove all vehicles and debris from the interstate in order to reopen it to traffic.

FHP did not specify what started the massive collision, saying once its large-scale investigation is concluded, it will have more data about what caused the chain-reaction crash.

However, the National Weather Service in Jacksonville had issued a dense fog advisory less than three hours earlier for much of northern Florida, including Columbia County where the crash occurred.

In the NWS Jacksonville's tweet at 10:56 p.m. on Dec. 31, forecasters wrote, "Firework smoke may mix with the fog resulting in localized Super Fog and near zero visibility! Drive with extreme caution."

The crash happened around 12:40 a.m., FHP said.

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At 5:49 a.m., NWS Jacksonville posted another tweet, again warning about "dangerous dense fog" for the area.

"Webcams showing a widespread dense fog with visibility to near zero in some areas," the weather service said. "This fog is dangerous to drive in! If possible, delay your travel until later this morning."

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Forecasters had been warning drivers about dense fog conditions in northern Florida for two days prior to the chain-reaction crash.