LOWELL -- Mambo Grill restaurant downtown is closed indefinitely to "improve operations," owner Franky Descoteaux told The Sun.

The status of the Mambo Grill, which serves Mexican food with a focus on burritos, had been uncertain all week. Multiple businesses in the surrounding area on Merrimack Street said the restaurant hasn't been open since Saturday.

The downtown Lowell was closed Thursday at lunchtime also.

The doors were locked and the lights were out as a "Closed" sign hung on the front door. No employees were in sight. The restaurant's tables and chairs were still set up inside and the walls were still lined with paintings.

"In light of the 10 great years we have had in downtown and the large number of loyal customers who have supported us for a decade, we have decided that it (is) time to rejuvenate Mambo Grill," said Descoteaux in an e-mail Thursday afternoon. "We are currently focused on taking some time to improve operations so that we can continue to serve our community."

Ani Vong, general manager of Humanity across the street from Mambo Grill, said she knew the restaurant was open on Saturday during the Lowell City of Lights parade but she didn't think it had been open since then. Descoteaux also owns Humanity, but Vong said she didn't know of any plans for the restaurant.

"We keep the two businesses separate, so I have no idea," said Vong. "I'm really just focused on making this business as successful as I can."

Co-owner of Eileen's Pizzeria and Deli Joe Curtis also said Mambo Grill, which abuts his own restaurant, hasn't been open since Saturday. He hasn't noticed an impact on his own business.

"It's really two different kinds of food," said Curtis. "She has her own loyal customers and I think we're just going for two different things."

Rumors have already started to spread about the fate of the Mambo Grill, which Descoteaux opened in 2004.

Scott Stacey, manager at La Boniche, believed the restaurant was shut for good and that it was set to be purchased by the owners of the Little Delights Bakery across the street.

However, Little Delights co-owner Lee Taing said the bakery wouldn't be purchasing the restaurant.

"There was talk about it, but I don't think we are going to," said Taing.

Joe Carreiro, business manager for the soon-to-be-opened El Potro Bar and Grill across the street, heard something else about Mambo Grill.

"We've been told they're just on vacation," said Carreiro.

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