WASHINGTON -- The United States launched a military strike Thursday on a Syrian government air base in response to a chemical weapons attack that killed dozens of civilians earlier in the week.
On Friday, there were reports the U.S. was investigating if Russia was complicit in the poison gas attack earlier in the week that killed dozens of Syrians.
On President Donald Trump's orders, U.S. warships launched 59 Tomahawk cruise missiles at the airbase that was home to the warplanes that carried out the chemical attacks, U.S. officials said.
The strike is the first direct military action taken by the U.S. against the regime of Syrian President Bashar al-Assad in the country's six-year civil war.
It represents a substantial escalation of the U.S. military campaign in the region, and could be interpreted by the Syrian government as an act of war.
Six people were killed in the airstrike, according to a televised statement by the Syrian's Armed Forces General Command. Russia condemned the strike as an "act of aggression," and Assad's office Friday called it "a disgraceful act" that "can only be described as short-sighted."
"Tonight, I ordered a targeted military strike on the air field in Syria from where the chemical attack was launched," Trump said during short remarks to reporters at Mar-a-Lago, where he ordered the strike just hours earlier. "It is in this vital national security of the United States to prevent and deter the spread and use of deadly chemical weapons.
"There can be no dispute that Syria used banned chemical weapons, violated its obligations under the Chemical Weapons Convention and ignored the urging of the U.N. Security Council. Years of previous attempts at changing Assad's behavior have all failed and failed very dramatically."
Lawmakers in the U.S. generally supported Trump's decision to strike back against Assad but cautioned the president against unilaterally starting a war without first consulting Congress.
A pair of defense hawks -- Sens. John McCain and Lindsey Graham -- who have frequently been critical of Trump, roundly praised his decision Thursday night.
"Acting on the orders of their commander-in-chief, they have sent an important message the United States will no longer stand idly by as Assad, aided and abetted by Putin's Russia, slaughters innocent Syrians with chemical weapons and barrel bombs," McCain and Graham said in a joint statement.
But Sen. Rand Paul called on Trump to consult on Congress.
"While we all condemn the atrocities in Syria, the United States was not attacked," Paul said. "The President needs congressional authorization for military action as required by the Constitution, and I call on him to come to Congress for a proper debate."
The U.S. began launching airstrikes in Syria in September 2014 under President Barack Obama as part of its coalition campaign against ISIS, but has only targeted the terrorist group and not Syrian government forces.