Fighters from the Iraqi pro-government forces inspect the damage at the Albu Aitha bridge north of Ramadi following an attack a military source said was carried out by the Islamic State (IS) group, on May 12, 2016. [Photo/VCG]

BAGHDAD - Islamic State insurgents killed at least 17 Iraqi soldiers with suicide truck bombs on Thursday in a major attack on government forces that recaptured the western city of Ramadi in December, military officials said.

The jihadist group also killed two policemen and wounded eight others in two suicide bombings in Abu Ghraib outside Baghdad, a day after killing at least 80 people in bombings at an outdoor market and two checkpoints inside the capital.

The attacks near Ramadi dealt one of the heaviest blows to the army since it drove Islamic State out of the western city five months ago.

An army colonel?said that militants killed at least 17 soldiers with suicide truck bombs in Jarayshi, 10 km (6 miles) north of Ramadi. They also surrounded an army regiment, seized a bridge and cut a key supply route linking Ramadi to the Thirthar district further north, army sources said.

Air strikes by a US-led coalition later allowed government forces to regain control of the supply route. But despite army reinforcements, the militants had dug into northern residential areas by nightfall and were lobbing mortars at government positions across the Euphrates river.

An officer said the Islamic State attack appeared designed to delay an expected army offensive that would have completely severed militant supply routes to Falluja on the western approaches to Baghdad, which Iraqi forces have ringed for more than six months.