After a swarm of jellyfish invaded Florida beaches and stung over 400 people last weekend, beach officials say that the waters appear to be much safer, just in time for the Labor Day weekend.

On Saturday, 257 people were stung by jellyfish on Daytona Beach, while another 184 were hit Sunday on New Smyrna Beach, reports the New York Daily News.

Fortunately, no one was seriously injured, and lifeguards were able to treat the stings with vinegar.

Beach officials, who have yet to identify the exact species of jellyfish that arrived on Friday, said that they "weren't typical-looking" jellyfish.

Volusia County Beaches officials raised purple and yellow flags to warm visitors about the "increased marine pests," says the county's Facebook page.

"They were all over and all in multiple sizes," beachgoer Michelle Craycraft told WFTV. "I didn't know what it was. I started looking at it and it was just really bizarre looking. Then it started to move."

"They're clear except for one little spot of color in the middle," Capt. Ray Manchester, with Volusia County Beach Safety, told WFTV.

However, Volusia County Beach Safety Captain Tammy Marris told USA TODAY that it appears the jellyfish have been carried back out to the ocean since there were only four reports of jellyfish stings on Monday.

Experts say that the swarm of jellyfish that invaded the county beaches is an usual occurrence that happens about a dozen times a year.

Two weeks ago, over 400 swimmers reported being stung by jellyfish in the same locations after a swarm invaded Volusia County beaches during a hot weekend, according to the Orlando Sentinel.

While most jellyfish stings are not severe, they can be life-threatening in rare case scenarios, according to the National Science Foundation.