ST. PETERSBURG, Fla. (AP) — The Memorial Day weekend marking the unofficial start of summer in the U.S. meant big crowds at beaches and warnings from authorities Sunday about people disregarding the coronavirus social-distancing rules and risking a resurgence of the scourge that has killed nearly 100,000 Americans.

Meanwhile, the White House announced a ban on travel to the U.S. from Brazil, which has been hard hit by the pandemic.

Sheriff’s deputies and beach patrols tried to make sure people kept their distance from others as they soaked up the rays on the sand and at parks and other recreation sites around the country.

In the Tampa area along Florida’s Gulf Coast, the crowds were so big that authorities took the extraordinary step of closing parking lots because they were full.

On the Sunday talk shows, Dr. Deborah Birx, coordinator of the White House coronavirus task force, said she was “very concerned” about scenes of people crowding together over the weekend.

“We really want to be clear all the time that social distancing is absolutely critical. And if you can’t social distance and you’re outside, you must wear a mask,” she said on ABC’s “This Week.”

In Missouri, people packed bars and restaurants at the Lake of the Ozarks, a vacation spot popular with Chicagoans, over the weekend. One video showed a crammed pool where vacationers lounged close together without masks, St. Louis station KMOV-TV reported.

In Daytona Beach, Florida, gunfire erupted Saturday night along a beachside road where more than 200 people had gathered and were seen partying and dancing despite the restrictions. Several people were wounded and taken to the hospital, authorities said.

“We got slammed. Disney is closed, Universal is closed. Everything is closed so where did everybody come with the first warm day with 50% opening? Everybody came to the beach,” Volusia County Sheriff Mike Chitwood said at a Sunday news conference, referring to crowds in the Daytona Beach area.

But officials in California said most people were covering their faces and keep their distance even as they ventured to beaches and parks. Many Southern California beaches were open only for swimming, running and other activities. Sunbathing and group activities such as volleyball were prohibited.

At New York’s Orchard Beach in the Bronx, kids played with toys, and people sat in folding chairs. Some wore winter coats on a cool and breezy day, and many wore masks and sat apart from others.

“Good to be outside. Fresh air. Just good to enjoy the outdoors,” said Danovan Clacken, whose face was covered.

The U.S. is on track to surpass 100,000 coronavirus deaths in the next few days, while Europe has seen over 169,000 dead, according to a tally by Johns Hopkins University that almost certainly understates the toll. Worldwide, more than 5.3 million people have been infected and 342,000 have died.

The New York Times marked the horror by devoting Sunday’s entire front page to a long list of names of those who have died in the United States. The headline: “An Incalculable Loss.”

Meanwhile, President Donald Trump, who went golfing for the second day in a row after not playing for weeks, said on the syndicated Sunday program “Full Measure With Sharyl Attkisson” that he is feeling fine after taking a two-week course of the unproven drug hydroxychloroquine and a zinc supplement.