Camp Taji hit again, four killed

Four Iraqi soldiers have been killed in a suicide bomber's attack near Camp Taji where Australian and New Zealand soldiers are based.

Twelve others were injured when the man blew himself up at the northern gate of the military base on Monday, according to reports.

No one had claimed responsibility for the attack, which followed the detonation of a car bomb southwest of the camp earlier this month which killed seven.

No New Zealand soldiers were hurt, Defence Minister Gerry Brownlee told RNZ.

The attack came as New Zealand announced it would be extending its initial two-year training assignment to Camp Taji by 18 months, out to November 2018.

About 100 New Zealand soldiers are at the massive American-controlled military complex north of Baghdad, helping Australian troops train Iraqi troops for the fight against Islamic State.