It was not immediately clear what became of the shooter.
North Atlantic Treaty Organisation did not release the identity of the American soldier killed or provide further details about where the incident took place.
The shooting happened at the airport in Tarinkot, the capital of Uruzgan province, a local police officer told AFP.
Pompeo said the proposed talks would be Afghan-led, with the USA playing a supporting role.
Maciel was part of Operation Freedom's Sentinel, which conducts counter-terrorism missions targeting terrorist groups like Al Qaeda and the Islamic State affiliate in Afghanistan and also focuses on building up local Afghan forces.
The incident marks the first combat fatality for the USA military in Afghanistan since April 30 and the second there this year.
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Trafford said Perkins Coie followed up on the May emails with a June 12 phone call that Jordan appears also not to have received. Three former wrestlers are claiming there's no way Jordan would have been unaware that Strauss was abusing members of the team.
North Atlantic Treaty Organisation said an investigation of the attack was underway.
He said the strategy announced a year ago by President Donald Trump of sending more troops to increase pressure on the Taliban and push them toward negotiations was working, and would reassure Afghans "that we will support them as they continue fighting to liberate their country and their people". The U.S. invaded Afghanistan following the September 11 terror attacks by al-Qaida, which the Taliban government at the time had harbored.
However, details of the attack's location were not revealed, reports The Washington Post. Afghan commandos carried out the operation with support from US special forces and air power.
Miller's deployment to Afghanistan, which would see him promoted to four-star general, comes at a time when local security forces are still struggling to contain a resurgent Taliban.
Afghan civilians increasingly found themselves in the crosshairs during an unusually intense period of fighting last winter. "The Taliban have gained ground, US airstrikes have spiked to put pressure on the group to negotiate, and civilian casualties have increased - partly due to those airstrikes but mostly because of Taliban attacks, and some ISIS attacks".