The video was captured while BBC Arabic journalist Maryem Taoumi was interviewing Faisal Al-Asil, of the Moroccan Agency for Sustainable Energy, at the time of the blast.
Taoumi is in the middle of asking a question when she is interrupted by a rattling sound. The video shows her looking up, then standing up a second before the wall of the office implodes with a loud roar, sending paper and debris everywhere.
The camera is covered by something red for several seconds while the roar and sounds of screaming are heard.
Al-Asil seems frozen in those first few seconds, but his face drops once the camera goes red. He then moves his camera to the side and a woman in a mask leans into view. Both of them look alarmed, and the woman puts her hand over her heart.
Taoumi can be heard groaning several times, then an alarm starts to sound inside the BBC Arabic bureau.
The journalist finally picks the camera up off the red carpet, flashing scenes of the ruined office and the desk under which she hid during the explosion.
The video ends with Taoumi emerging from under the desk and declaring that she is fine.
The whole incident unfolded in under a minute on Tuesday.
The massive explosion occurred around 6 p.m. local time after a fire at the port in Beirut. Various eyewitness videos show a large plume of smoke rising from the port area just before the blast, which created a huge mushroom cloud over the area.
The BBC Arabic office is roughly 1.5 kilometres southwest of the explosion site, Google Maps shows.
The blast was caused by about 2,750 tonnes of ammonium nitrate that had been unsafely stored at a warehouse in the area, Lebanon’s President Michel Aoun said. The chemical can be used as a fertilizer or an explosive.
American domestic terrorist Timothy McVeigh used roughly two tonnes of ammonium nitrate in the 1995 Oklahoma City bombing. The bomb, which also included diesel and other chemicals, killed 168 people and destroyed about one-third of its target, the Alfred P. Murrah Federal Building.
The Beirut blast on Tuesday wiped out several city blocks, killed more than 100 people and injured thousands more. The shock wave rippled out across several kilometres, smashing through walls nearby and shattering windows farther away.
Eyewitness videos have continued to surface in the aftermath of the explosion. Many show the explosion or the aftermath, while others show what happened when the blast hit people indoors.
One such video shows the moment when the blast wave hit a church in the middle of a live-streamed service.
The video shows the camera rattling and the lights going out moments before the ceiling collapses. A piece of debris appears to fall on the priest as he dashes for cover.
— Rayane Moussallem (@RioMoussallem) August 4, 2020
The shock wave from the blast was felt as far away as Cyprus, an island roughly 200 kilometres away.
The city has seen devastation before. It was rocked by a 15-year civil war that ended in 1990, and has seen several terror attacks and clashes with Israel.
Officials say Tuesday’s explosion was the worst the city has ever seen.
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