A Syrian former regime official suspected of leading a notorious civilian massacre revealed by the Guardian – and who became one of the country’s most-wanted fugitives after the fall of Bashar al-Assad – has been arrested by security forces, Syria’s interior ministry announced. Amjad Youssef was captured in the Ghab plain area about 30 miles (50km) outside the city of Hama and had “been taken into custody following a carefully executed security operation”, the interior minister, Anas Khattab, said in a social media post on Friday. Mugshots released by the ministry showed Youssef, 40, in a striped prison uniform, while videos circulated on social media showing the former military intelligence officer in custody in a vehicle, his face bloodied, being sworn at and slapped by uniformed men.…