KABUL, Afghanistan — The top United States commander in Afghanistan confirmed that a rocket went astray during operations in the Marja area of Helmand province, killing 12 civilians, according to a statement issued by the International Security Assistance Force and the Afghan Ministry of Defense.

Gen. Stanley A. McChrystal, the ISAF commander, ordered the withdrawal of the type of rocket launcher used in the incident, a high-mobility artillery rocket system (HIMARS), from operations “until a thorough review of this incident has been conducted,” the statement said.

The American commander, who has made reducing civilian casualties a cornerstone of his policy in Afghanistan, apologized to President Hamid Karzai for the incident. “We deeply regret this tragic loss of life,” General McChrystalsaid. “The current operation in central Helmand is aimed at restoring security and stability to this vital area of Afghanistan. It’s regrettable that, in the course of our joint efforts, innocent lives were lost.”