By Laila Kearney
(Reuters) - The Washington Monument will remain closed indefinitely due to elevator malfunctions that have forced several closures of what is one of the U.S. capital's most popular tourist attractions, the National Parks Service said on Monday.
The 555-foot (169-meter) monument, erected in honor of President George Washington in the 19th century, was scheduled to have opened in mid-September after its most recent closure began on Aug. 17.
"Despite the continuing work on the Washington Monument elevator, we have not been able to determine the causes of the ongoing reliability issues," the National Park Service, which oversees the monument, said in a statement. "As a result, we have made the difficult decision not to reopen the Washington Monument until we can modernize the elevator control system."
Electrical short-circuiting has forced the closure of the marble obelisk about two-dozen times since it reopened in May 2014 following repairs for earthquake damage sustained in 2012.
In an incident in August, tourists in the monument's elevator were forced to exit using stairs because the elevator doors failed to open.
Work will continue on the monument, which attracts about 600,000 visitors a year, for an unknown period of time, the Parks Service said.
The agency said it expected to announce additional details about the work and duration of the closure in the next couple of weeks.
(Reporting by Laila Kearney; Editing by Bill Trott)