U.S. officials have obtained blood and urine samples from victims of the alleged chemical attack in Syria, and they say the samples show proof that chlorine and nerve agents were used in the attack.
According to NBC News, the officials said they were “confident” that the samples showed evidence of chemical components, but they weren't entirely sure.
U.S. and international intelligence has also reportedly been gathered as proof that the Syrian government was behind the attack on the rebel-held territory.
The attack is the latest in a series of aggressive bombings in Douma, where Russian-backed forces have been working to eradicate Syrian rebels.
The results of the samples will be presented to President Donald Trump as U.S. military forces weigh options for retaliation against the Assad regime in an effort to deter future use of chemical weapons.
Defense Secretary Jim Mattis on Thursday told Congress that the military is waiting on evidence before carrying out a retaliatory attack on Syrian government forces, a move Trump has hinted at throughout the week.
“I believe there was a chemical attack, and we’re looking for the actual evidence,” Mattis said.
Mattis added that while no decision has been made yet, the National Security Council will be meeting on Thursday to discuss options and next steps as the U.S. prepares to respond.
Trump swiftly condemned the attack on Sunday, specifically calling out Russian President Vladimir Putin and Syrian President Bashar Assad. After a similar attack last year, Trump ordered a missile strike on an airbase in Syria in retaliation, and he promised to respond strongly to the latest act of Syrian aggression.
Many dead, including women and children, in mindless CHEMICAL attack in Syria. Area of atrocity is in lockdown and encircled by Syrian Army, making it completely inaccessible to outside world. President Putin, Russia and Iran are responsible for backing Animal Assad. Big price...
— Donald J. Trump (@realDonaldTrump) April 8, 2018
And with the new evidence that the attack involved chemicals and that Syrian government forces perpetuated it, the president is inching closer to deciding on an appropriate military response.