SAN DIEGO, Calif (Reuters) - A roof collapsed at the world's busiest border crossing between Mexico and the United States on Wednesday, injuring 17 travelers and construction workers and closing the port of entry to northbound traffic, authorities said.
The U.S. Customs and Border Protection agency said scaffolding supporting the roof at the San Ysidro port of entry, linking Tijuana, Mexico, with San Diego, California, collapsed across several lanes of traffic at 10:45 a.m. local time.
"CBP officers were processing vehicle traffic in those lanes at the time of collapse, and there were vehicles located under the collapsed area," CBP spokeswoman Jacqueline Wasiluk said in a statement.
"Seventeen people were injured, including travelers and construction workers, with most treated on site," she added.
Of the 17 injured, three were transported to local hospitals for treatment, she said, although the extent of their injuries was not immediately clear.
The San Ysidro port of entry is the world's busiest border crossing, handling over 50,000 vehicles each day crossing north from Tijuana, along with 25,000 pedestrians.
It has been undergoing a $600-million upgrade since February that aims to more than double its capacity. It was not clear if the collapse was linked to the expansion work.
Wasiluk said the crossing remained closed to northbound vehicle and pedestrian traffic, and travelers were being diverted to the nearby Otay Mesa port of entry a few miles to the east. The southbound crossing to Mexico remains open.
Authorities had no estimate of when the border crossing will be reopened, and Wasiluk urged travelers to wait to cross north.
(Additional reporting by Lizbeth Diaz in Tijuana; Writing by Tim Gaynor; Editing by Greg McCune)