The US has admitted carrying out an attack in eastern Syria that killed dozens of Syrian forces fighting so-called Islamic State (IS).
The US-led coalition said the “mistake” on 17 September was intended to target IS positions.
Coalition aircraft from the UK, US, Denmark and Australia were involved in the attack near Deir al-Zour.
Syrian President Bashar al-Assad has maintained that the deadly airstrikes were intentional.
The attack, which the Russian army says killed at least 62 Syrian troops, were halted when Russia informed the US it was hitting Syrian forces.
“In this instance, we did not rise to the high standard we hold ourselves to, and we must do better than this,” said US Lieutenant-General Jeff Harrigian.
A spokesman for US Central Command (Centcom), the wing of the American military in charge of all its Middle East forces, said the mistake was “regrettable”, adding that it was not the intent to target Syrian …