Welcome back to Market Basket. It’s OK to shop again.

Employees and customers at the supermarket chain’s Biddeford store on Thursday morning celebrated a hard-won victory that has placed former CEO Arthur T. Demoulas back in charge.

Wednesday night, the board of directors of Demoulas Super Markets Inc., which owns 71 Market Basket stores in New England, announced that it had reached an agreement to sell a controlling share of the company to Demoulas, ending a six-week boycott of the chain.

As each furloughed employee returned to the Biddeford store Thursday, an announcer on the public address system welcomed them back.

“There will be a party atmosphere today,” said cashier Nancy Wedge, whose work schedule had been cut from 30 hours a week to just eight during a highly effective customer boycott that helped pressure the board into meeting employees’ sole demand: Bring back Arthur T.

Demoulas made a triumphant return Thursday, speaking from the back of a truck to workers and customers celebrating at a rally outside the chain’s headquarters in Tewksbury, Massachusetts.

“I am in awe of what you have all accomplished,” he told the crowd.

“We did it for you!” one employee yelled back. “We love you!” shouted another.

In Biddeford, shoppers Michael and Sandy Jubinski brought balloons and a card for the store’s employees. The couple, who own Stone Turtle Cooking and Baking School in Lyman, participated in the boycott even though they hated patronizing Market Basket’s competitors.

“Shopping sucked everywhere else,” Sandy Jubinski said. “I feel like I got sent to jail.”

Biddeford store director Micum McIntire said it would take some time for the store’s shelves to be completely restocked after a walkout by delivery drivers that effectively cut off shipments of many items, particularly perishables such as fresh meat and produce.

On Thursday, shipments of some missing goods already were rolling in.

“I have eggs, I have meat, I have milk,” McIntire said. “I’m open for business.”

Produce will take the longest to replenish because it comes in shipments from California, he said.

Despite a number of still-empty aisles, customers who had heard about the boycott’s conclusion came in droves to congratulate employees – and shop. At 11 a.m., sales already were up 90 percent compared with a typical day during the boycott, McIntire said.

“I just came by today to say ‘Hi’ to everybody and to see if it was real,” said Alfred resident and Market Basket shopper Barbara Alho.

Instead of shopping at another supermarket during the boycott, Alho relied on food she already had at home.

“I have a freezer and, believe it or not, I had a lot of stuff,” she said.

Of the Biddeford store’s 270 part-time employees, only 10 had quit and found other jobs, McIntire said. The rest will be returning to work.

He said there were celebrations going on at Market Basket locations all over New England.

“My wife was in the Portsmouth (New Hampshire) store, and they were already drinking champagne at 7 o’clock this morning,” McIntire said.

Wednesday night’s deal reportedly gives Demoulas full authority to manage the supermarket chain, including the Biddeford store. The chain employs 25,000 full- and part-time workers. Arthur T. Demoulas and his sisters already own 49.5 percent of Market Basket. Now, they will buy out the 50.5 percent of the company controlled by their rival cousin, Arthur S. Demoulas, for $1.5 billion.

Arthur T. and his management team will return to oversee day-to-day operations while the transaction to purchase the company is completed. The current co-CEOs, business consultants Felicia Thornton and Jim Gooch, will remain in place pending the closing, which is expected to take several months.

The deal follows several weeks of firings, furloughs, walkouts and protests by thousands of workers, who called for the board of directors to reinstate “Artie T.” Thousands of part-time workers were taken off the schedule indefinitely as a result, including about 270 workers at the Biddeford store.

Market Basket employees do not belong to a union, but nonetheless they organized an effective disruption of the business that gave the board little choice but to meet their demands. The successful customer boycott they initiated was costing the company millions of dollars in revenue each day, according to analysts.

Sandy Jubinski said she was thrilled about the unprecedented display of solidarity among store employees and customers that led to Wednesday night’s victory.

“We’re just really proud of these guys, and we’re really proud of the public for supporting them,” she said.