US President Donald Trump called the operation a success...
The White House pushed back against suggestions that Trump had broadcast his plans for military strikes via Twitter...
Initial US assessments have been unable to determine conclusively what materials were used in the attack...
Russia has denied any involvement in the attack and has said it suspects the British secret services of using the Novichok nerve agent...
Inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW) began running independent tests...
