A bizarre environmental mystery is unfolding along Florida’s coast as thick, black tar balls have washed ashore, forcing several beaches to close. The U.S. Coast Guard has launched an investigation, but so far, the source of the contamination remains unknown.

Beachgoers from Palm Beach down through Miami have been met with an unwelcome surprise—sticky, oily globs clinging to the sand and their feet. In Fort Lauderdale, lifeguards and fire rescue crews quickly realized the severity of the situation after reports of an unknown substance near Las Olas Boulevard.

Officials shut down a large stretch of beach, warning swimmers to stay out of the water while they assessed the damage. “We are asking beachgoers to remain out of the water,” Fort Lauderdale Fire Rescue announced. “Beachgoers are welcome to enjoy the beautiful day, but we are monitoring the situation closely.”

The Coast Guard deployed both air and ground crews to survey the coastline, scouring the waters for any sign of a spill. “The source remains unknown,” the agency confirmed, but promised continued assessments as they work with local government agencies to coordinate future cleanup efforts. Federal and state officials, including the Department of Environmental Protection, are now working to determine whether the contamination poses a larger environmental threat.

While some beaches in Hollywood, Deerfield Beach, Boca Raton, and Pompano Beach also reported tar balls, the impact wasn’t as severe as in Fort Lauderdale.

(MORE: Black Sludge Shuts Down Picturesque Beach)

With Florida’s coastlines already vulnerable to environmental disasters, officials are preparing for a potentially complicated cleanup in the affected areas. But with no answers yet, the focus now shifts to damage control - safeguarding residents and tourists, protecting the waters and marine life and ensuring that Florida's world famous beaches don't stay closed for long.

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