Reuters) – Sunny days and warm weather are proving to be as challenging to manage as restaurants, hair salons and other businesses, as about half of U.S. states partially reopen their economies after the coronavirus lockdown.On Saturday, thousands of people gathered on the National Mall in Washington to view a U.S. Navy flyover to honor healthcare workers and others battling the pandemic.

In New York City, the warmest weather yet this spring caused picnickers and sunbathers to flock to green spaces in Manhattan, including crowded conditions at the Christopher Street Pier in Greenwich Village, according to photos on social media.

Last week, California ordered beaches in Orange County to close, after crowds defied public health guidelines to throng the popular shoreline. Police in the county’s Huntington Beach said people were complying on Sunday.

New York Mayor Bill de Blasio said there were “some real issues” near the pier and police would increase patrols.

Dr. Deborah Birx, response coordinator for the White House coronavirus task force, said on “Fox News Sunday” that massing on beaches was not safe unless people kept at least 6 feet (1.8 m) apart. She also weighed in against allowing such businesses as beauty salons and spas to reopen in the first phase.

“We’ve made it clear that that is not a good phase one activity,” she said, as the number of U.S. cases topped 1.1 million and the death toll rose to more than 67,000 on Sunday.

Protesters gathering, as they did last week in Michigan and other parts of the country to demonstrate against stay-at-home restrictions, posed a huge risk, she said.

“It’s devastatingly worrisome to me personally if they go home and infect their grandmother or their grandfather who has a comorbid condition and they have a serious or a very – or an unfortunate outcome, they will feel guilty for the rest of our lives,” Birx said.

Scott Gottlieb, a former Food and Drug Administration commissioner, said on Sunday the country was seeing a “mixed bag” of results from coronavirus mitigation efforts. He said there were about 20 states seeing a rising number of new cases including Illinois, Texas, Maryland, Indiana, Virginia, North Carolina and Tennessee. Virginia reported a record number of deaths on Sunday, up 44 for a total of 660.