Washington (CNN) -- Defense Secretary Robert Gates apologized to a Pakistani general Wednesday for the recent deaths of Pakistani border guards in a U.S. helicopter strike, a Pentagon spokesman said.
Pakistani Gen. Ashfaq Parvez Kayani met Wednesday morning with Gates, Joint Chiefs of Staff Chairman Adm. Mike Mullen, and other officials in Washington.
The deaths prompted the Pakistanis to temporarily close a crossing used by trucks that haul material to NATO-led troops from Pakistan into Afghanistan.
NATO's International Security Assistance Force said two guards died last month in a U.S. helicopter strike when the crew mistook them for insurgents and fired at them over the Afghan border in Pakistan.
Gates called the deaths "unintentional," said Pentagon spokesman Geoff Morrell.
He said the officials also discussed ways of improving military coordination along the border between Afghanistan and Pakistan, as well as the long-term relations between the United States and Pakistan.
CNN's Larry Shaughnessy contributed to this report