The Kingdom Center skyscraper in Riyadh told people employed there to work from home due to possible attacks by Yemen's Houthirebels.
The 99-storey tower is one of Saudi Arabia's tallest buildings.
Kingdom Center made working from home "mandatory" with no reason given. The new order is effective immediately and will be in power until further notice, the building's management told tenants, AFP reported.
Among the building's tenants are important financial institutions such as the International Monetary Fund, as well as wealth management company Merril Lynch.
At the building's foot is a shopping center, which will remain open for now.
Attacks increase
Studies in schools across Saudi capital Riyadh and the surrounding areas will take place online for a second week, with the city's King Khalid International Airport still being closed after a Houthi attack resulted in 13 casualties.
The conflict between the Saudi-led coalition and Iran-backed Islamist group Houthis has continued to escalate, with the coalition reporting its first military deaths since the escalation's beginning.
Two helicopter pilots were killed near the Yemen border due to a "technical malfunction," the coalition said, with the Houthis earlier announcing the downing of an Apache helicopter "belonging to the Saudi enemy," the group said.
Conflict flares up again
On the Saudi side, two drones were intercepted over Riyadh overnight, with a third being shot down over the country's Eastern Province, a known oil-rich area, according to the authorities in the country.
Two ballistic missiles were also intercepted in Saudi Arabia's south.
The two sides have been confronting each other on various intensities over the past decade. After a four-year ceasefire, the conflict between the two sides saw an escalation after the Yemen-based Islamist militia took over strategic territory along the Red Sea coast last month.
The Houthis have targeted oil facilities, tankers and Riyadh's international airport, with the coalition carrying out strikes on Houthi areas.
Edited by: Jenipher Camino Gonzalez
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