US air strike killed 23 Afghan civilians, says UN
Most of the dead were women and children.
On Tuesday a helicopter hit a compound during a joint operation with US and Afghan forces in Garmsir district in Helmand.
The US military is taking a more aggressive approach against the Taliban to force them to a peace table, meaning a surge in air operations.
The UN Assistance Mission in Afghanistan noted a sharp increase in civilian casualties from air strikes and said it was particularly concerned that children were "disproportionately impacted".
According to UN figures, there were 649 civilian casualties from air strikes in the first nine months of the year, more than in any entire year since at least 2009, when UNAMA began systematic documentation of casualty figures.
In the same period, US aircraft unleashed more than 5,200 weapons, more than any other year since 2011.
This year broadly has also proved to be the deadliest for Afghan civilians. Suicide bombs caused more than 2,300 civilian casualties so far, more than any other tactic, including ground fighting, according to a recent UN report.
Agencies contributed to this report.
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