Kabul, Afghanistan (CNN) -- A roadside bomb exploded in southern Afghanistan's Kandahar province as a joint NATO-Afghan security patrol arrived to defuse it, killing seven Afghans and one U.S. soldier, a district official said Sunday.
The explosion occurred Saturday in the village of Kuhak in Arghandab district, Shah Muhammad, the district chief administrator, said. The district has long been considered a Taliban stronghold, and it neighbors the Panjwai district where an Army staff sergeant allegedly went on a shooting rampage that left 17 people dead.
Six members of the Afghan police, a translator and a U.S. soldier were killed Sunday, Muhammad said. The district's police chief, Niaz Muhammad, confirmed the number of casualties.
"The police were told there is an IED. When they reached the area to defuse it, the bomb exploded," Muhammad said.
The bomb was possibly remotely detonated, he said.
The explosion follows a threat a day earlier by the Taliban, who vowed in an e-mail to CNN to take "strong revenge" for the March 11 shootings in the Panjwai district. The Taliban claimed justice won't be served in U.S. courts which they said "are not reliable."
The group, which been battling coalition and Afghan government forces for years, believes that "tens of American soldiers, and not one person" are responsible for the killings, according to the message.
Staff Sgt. Robert Bales has been charged with 17 counts of murder, six counts of attempted murder and two counts of assault in the attack.
CNN's Mitra Mobasherat and Ruhullah Khapalwak contributed to this report.