"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," Obama said
in a written statement, according to Sky News.
"The 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."
The President also offered his full support in a US investigation into this matter, and has vowed to hold anyone responsible for this incident accountable.
President Obama has also called Afghan Presient Hamid Karzai to "express his shock and sadness" over what happened and to reaffirm the "deep respect" the US has for the people of Afghanistan, CNN reports.
President Karzai condemned the attack and had demanded an explanation earlier Sunday. Karzai deemed the incident an assassination and said it was unforgivable.
US Defense Secretary Leon Panetta has announced that an investigation is already underway.
"A suspect is in custody, and I gave President Karzai my assurances that we will bring those responsible to justice," Panetta said
, as Sky News writes.
He also expressed his shock and sadness over the suspect being a US service member, and said the soldier was "clearly acting outside his chain of command."
Mr Panetta also said he told Mr. Karzai "that the American people share the outrage felt by the Afghan leader and his people."
The massacre in Kandahar follows a recent outbreak of anti-US violence and rioting in Afghanistan over the accidental burning of Korans by US troops last month.