Blast kills 4, wounds 14 on Afghanistan's Bagram Airfield

Four people were killed and about 14 others wounded in an attack early Saturday on Afghanistan's Bagram Airfield, the U.S. military there said.

At about 5:30 a.m. local time, an explosive device was detonated on Bagram, one of the U.S. military's remaining major installations there, according to a statement released by Resolute Support officials.

No additional information was available, including whether the casualties were service members or Americans. Response teams at Bagram were continuing to treat the wounded and investigate the incident, officials said.

"To the family and friends of those who lost their lives today, we share your loss, and our thoughts are with you," said Gen. John Nicholson, the top U.S. commander in Afghanistan, in a statement. "For the family and friends of those wounded in today's attack, let me assure you they are receiving the best care possible, and we will keep them in our thoughts today."

Nicholson went on to say that the attack will not deter the U.S.-led NATO mission to train, advise and assist the Afghans to "create a better Afghanistan."

The Taliban claimed responsibility for the attack, which they said was carried out by a suicide bomber inside the base, the Associated Press reported. A spokesman for the insurgent group said the attack had been planned for four months, according to the AP.

Bagram Airfield, which was a major hub for U.S. troops throughout the war, is one of the few installations still being used by U.S. Forces-Afghanistan and Resolute Support.

At the height of the war, there were more than 800 bases and outposts across the country. But as the U.S.-led coalition handed over security responsibility to Afghan forces, it began to close or hand over most of its bases. Today, only a few key ones remain, including Bagram, Kandahar Airfield and a cluster of bases in Kabul.