Anti-American sentiment in Afghanistan could continue to grow after a U.S. solider killed 16 civilians and wounded others in their Kandahar province homes Sunday morning.

The soldier left his military base earlier in the morning and fired on two homes, according to the BBC. Afghan President Hamid Karzai announced that nine children and three women were among those killed by the soldier, who has been detained by authorities. Karzai also called the shooting "an assassination" and demanded an explanation from the U.S.

U.S. Ambassador James Cunningham released a statement about the incident.

"The United States extends its deepest condolences to the families of the victims of today's tragic shooting incident in Kandahar province," he said. "We are saddened by this violent act against over Afghan friends. Our thoughts and prayers are with the families and their entire community. The incident is under investigation."

The incident comes a few weeks after some U.S. soldiers were caught burning copies of the Quran in Afghanistan.


Update: President Barack Obama released a statement on the incident.

"I am deeply saddened by the reported killing and wounding of Afghan civilians," he said. "I offer my condolences to the families and loved ones of those who lost their lives, and to the people of Afghanistan, who have endured too much violence and suffering. This incident is tragic and shocking, and does not represent the exceptional character of our military and the respect that the United States has for the people of Afghanistan. I fully support Secretary Panetta’s and General Allen’s commitment to get the facts as quickly as possible and to hold accountable anyone responsible."

This post has been updated from its original version.

WATCH: Video from the Associated Press, from March 11, 2011.