01:50 - Source: CNN
Here's what we know about the Beirut explosion
Wasnington CNN  — 

Defense Secretary Mark Esper said Wednesday that “most believe” that the explosion in Beirut “was an accident, as reported,” despite President Donald Trump’s claim a day prior that it was an attack.

The US is “still getting information on what happened” in regard to the blast in the Lebanese capital, Esper said. US defense officials also told CNN there was no indication the explosion was an attack, despite Trump’s assertion Tuesday.

Esper’s remarks came as part of a discussion at the annual Aspen Security Forum, where he said he spoke about the blast with Secretary of State Mike Pompeo Wednesday morning.

“We’re reaching out to the Lebanese government, have reached out. We’re positioning ourselves to provide them whatever assistance we can, humanitarian aid, medical supplies, you name it, to assist the people of Lebanon,” said Esper.

On Wednesday, Pompeo spoke with Lebanese Prime Minister Hassan Diab, expressing his condolences and pledging assistance in the wake of the explosion that rocked Beirut Tuesday.

“The secretary reaffirmed our steadfast commitment to assist the Lebanese people as they cope with the aftermath of this terrifying event,” a readout from State Department Principal Deputy Spokesperson Cale Brown said. “Secretary Pompeo further stressed our solidarity with and support for the Lebanese people as they strive for the dignity, prosperity, and security they deserve.”

Although the cause of the blast is unclear, Diab said Wednesday that about 2,750 metric tons of ammonium nitrate, a highly explosive material, had been stored at a port warehouse for the past six years “without preventive measures.”

The Prime Minister has launched an investigation into the deadly explosion which has claimed at least 135 lives, including one US citizen, and injured thousands.

“I will not rest until we find those responsible for what happened, hold them accountable, and impose maximum punishment,” Diab said in a statement, added it was “unacceptable” that so much ammonium nitrate had been stored “while endangering the safety of citizens.”

Trump on Tuesday evening referred to the incident as a “terrible attack.”

“It would seem like it based on the explosion,” Trump said. “I’ve met with some of our great generals and they just seem to feel that it was not a – some kind of manufacturing explosion type of event. This was a – seems to be according to them, they would know better than I would, but they seem to think it was an attack. It was a bomb of some kind.”

However, three US defense officials told CNN Tuesday there was no indication that the explosion was an attack.

CNN’s Barbara Starr, Ryan Browne, Nikki Carvajal, Jessie Yeung and Luke McGee contributed to this report.