Two New York Times journalists have been injured in Iraq after a helicopter carrying aid to refugees on Mount Sinjar crashed.

Correspondent Alissa J. Rubin and freelance photographer Adam Ferguson were on board the Iraqi military aircraft when it came down.

It is reported the pilot was killed in the crash and 20 passengers were injured.

In a statement, the New York Times says the two journalists have been airlifted out of the region to receive medical care.

Ms Rubin suffered concussion and broken wrists.

The Mi-17 helicopter was delivering aid to the minority Yazidi sect on the mountain. Reports say it crashed after too many refugees tried to climb on board.

The United Nations says up to 35,000 refugees have escaped Mount Sinjar and are "exhausted" and "dehydrated".

Thousands, who faced starvation on the mountain, managed to reach northern Iraq's Kurdistan region through Syria over the past three days.

"The new arrivals are exhausted, dehydrated and many have suffered sun or heat stroke, with the daily temperatures reaching 40C to 45C," said UNHCR spokesman Adrian Edwards.

An estimated 20,000 to 30,000 people remain trapped on the mountain without food, water or shelter.

Tens of thousands of Yazidis fled to Sinjar after Islamic State fighters gave them an ultimatum to convert to Islam or die.

The Iraqi military as well as the US and UK have been flying supplies to help them.

Elsewhere in Iraq, two car bombs killed 12 people in Baghdad, police sources said. A witness said he saw black smoke rising from the Karada area of the capital.

Channel 4's Jonathan Rugman is in Northern Iraq. He told Newstalk Breakfast earlier the situation for refugees is becoming increasingly desperate:

Originally published 7:42am