Hopes started to fade Saturday that a survivor would be found as rescue workers dug through the rubble of a devastated Beirut building, three days after a faint pulsing signal was detected.
Rescue workers, including teams from Chile, Venezuela and the Red Cross continued to search the ruins of the building in the Gemmayzeh neighborhood early Saturday morning, but hours into the operation they had yet to locate anyone.
The building was one of thousands destroyed when nearly 3,000 tons of ammonium nitrate exploded at the Beirut port. The enormous blast killed 191 people and injured 6,000 others and is considered to be one of the biggest non-nuclear explosions ever recorded.
Hopes were raised Thursday when a rescue dog called "Flash" — now hailed as a hero on social media in Lebanon — appeared to detect signs of life. Sensors and audio equipment later recorded a pulse of around 18 to 19 beats per minute and slow breathing beneath the rubble.
The beats dropped to seven per minute, local reporters at the site were told Friday, but by then the story had transfixed the nation, desperate for some good news.
As workers were using shovels and their hands to pick through debris, while mechanical diggers and a crane lifted heavy stone, George Abou Moussa, director of Lebanon's Civil Defense told Reuters on Saturday that the building was "really crumbling."
"It's scary and there's a lot of danger to the team," he said. But he insisted "always in search operations like this, you can neither lose hope nor absolutely say there is hope."
The Chilean group involved in the rescue effort have been part of multiple international searches, including the earthquakes in 2010 in Chile. It is also credited with rescuing 14 people found after the 2010 earthquake in Haiti — one of them 28 days after it struck.
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On Friday, the Lebanese capital came to a standstill observing a moment of silence, one month after the deadly blast. Many lit candles and said prayers.
The country was already crippled by a spiraling economic crisis and the explosion stoked public anger further at political elites, triggering the downfall of the government that many accuse of negligence and corruption.
Although the exact trigger of the blast remains under investigation, Lebanese officials in the aftermath blamed 2,750 tons of ammonium nitrate stockpiled in a port warehouse.
Reuters and the Associated Press contributed to this report.