US Troops Arrive In Baghdad On ISIS Mission

The first team of American military advisers has arrived in Iraq to help the country tackle the threat from Islamist insurgents.

About 40 of the 300 expected to be deployed to the Middle Eastern country were described by the Pentagon as having "started their mission".

Admiral John Kirby told reporters that two "initial assessment teams" have been deployed in Baghdad.

He said their role would be to assess the Iraqi army and not to engage in attacks on militants from the Islamic State of Iraq and Syria (ISIS), who have seized several towns north of Baghdad.

Admiral Kirby said: "This isn't about rushing to the rescue.

"These teams will assess the cohesiveness and readiness of the Iraqi security forces ... and examine the most effective and efficient way to introduce follow-on advisers."

In addition to the first 40, about 90 troops are thought to have arrived to set up a joint operations centre. Another 50 are expected to join them shortly.

It came as Iraqi air strikes killed at least 38 people in their battle to hold off the advancing ISIS forces.

Militants had launched a push to seize Iraq's largest oil refinery, located near Baiji, but the attack was repelled.

The refinery provides up to 50% of Iraq's demand for petroleum products until it stopped production as Sunni fighters launched attacks on the site.

Jihadists from ISIS have overrun several towns and cities in the north of the country.

Security forces, who turned and ran when the invasion started, are struggling to hold ground.