(CNN) -- Five troops killed in a suicide bombing this weekend at a military base in eastern Afghanistan were members of the U.S. Army's 101st Airborne Division, a senior U.S. military official said Sunday.
Earlier, authorities had said only that five members of NATO-led International Security Assistance Force, which includes troops from the United States and other nations, were killed in the Saturday incident.
The families of all five have been notified of the deaths, and a formal announcement from the Army is forthcoming, said the official, who declined to be identified pending the announcement.
On March 29, the same Army division lost six troops in a series of firefights in eastern Afghanistan.
On Saturday, a suicide bomber wearing an Afghan military uniform struck, killing the five, at a military base, Forward Operating Base Gamberi, in eastern Afghanistan's Laghman Province. The attack came during a meeting between Afghan soldiers and their ISAF mentors.
Four Afghan National Army troops were also killed and eight others, including four translators, were wounded, Gen. Mohammad Zahir Azimi said in a statement. The wounded were all in good condition, Azimi said.
Taliban spokesman Zabiullah Mojahed claimed 12 foreign soldiers and four Afghan military service members died in the attack. He said the bomber, Abdul Ghani, "joined the Afghan National Army a month ago in order to kill the invaders."
The Laghman Province base is controlled by Afghan security forces. Azimi said Saturday he would not comment on the Taliban spokesman's claim.
While clear progress is being made security-wise in eastern Afghanistan, civilians are under duress, according to the U.S. military official.
In February and March of this year, insurgent attacks on civilians increased 330 percent compared to the same period last year, the official said. In February and March 2010, insurgents injured or killed 82 civilians; this year, the total for those two months was 353 civilians.