Major Trey Cate of the 101st Airborne Division said on Tuesday soldiers at the base in Tallafar, west of the city of Mosul, fired on the vehicle when it failed to stop at an entry point.
The vehicle then blew up, he said. "The vehicle did not stop, so soldiers fired on it. It then detonated. None of the injuries are life-threatening," said Cate, adding it appeared to be a "suicide bomb" attack.
Four soldiers with the worst injuries had been transferred to the 21st combat support hospital in Mosul, 65 kilometres away.
Tallafar is mainly populated by Shia Turkmen and has been
calm since the US ousted president Saddam Hussein in April.
Three US soldiers killed
Also, three US soldiers died in a road accident north of Baghdad, a US military spokesman said on Tuesday.
The accident, which left one wounded, occurred during a combat patrol northeast of al-Duluiyah on 8 December, said 4th Infantry Division spokesman Colonel Bill MacDonald.
"Two Striker infantry carrier vehicles were travelling on a rural
road when the embankment collapsed causing them to roll over into a canal," he said.