DUBAI, United Arab Emirates – The world’s tallest skyscraper, Burj Khalifa, has unexpectedly closed to the public.The electrical problems are at least partly to blame for the closure. The indefinite closure, which began Sunday, nagging questions about its financial health.

Many visitors, thousands have lined up for the chance to buy tickets for viewing times often days in advance that cost more than $27 apiece.Now, they must get back in line for refunds. They are being offered the chance to rebook or receive refunds.

“It’s just very disappointing,” said Wayne Boyes, 40, tourist from near Manchester, England who showed up at the Burj’s entrance Monday with a ticket for an afternoon time slot only to be told the viewing platform was closed. “The tower was one of my main reasons for coming here,” he said.

Dubai opened the skyscraper on Jan. 4 in a blaze of fireworks televised around the world. The building had been known as the Burj Dubai during more than half a decade of construction, but the name was suddenly changed on opening night to honor the ruler of neighboring Abu Dhabi.

The building has not been confirmed yet to be reopen.