This story was written based on data published by the US Air Forces Central Command (Afcent), which it has since changed. Every month, Afcent releases figures on its air war in Afghanistan, including the number of weapons released - this includes bombs dropped, missiles released and rounds fired by jets, drones and gunships. The data published for September originally said 751 weapons had been released over the country but in late October this was quietly changed to 414. This significant reduction makes the below article inaccurate.

The Bureau approached Afcent for an explanation. A spokesperson said the mistake was because they had incorrectly recorded the number of 20mm rounds fired by USAF F-16 jets. They had counted each round fired as a single weapon released in the monthly summary whereas they should have counted every 100 rounds as one weapon released. It is not immediately clear how this explanation matches the difference in numbers. 

Despite the US dropping more bombs and missiles on Afghanistan in September than in any other month for nearly seven years, the number of US strikes in Afghanistan dropped. 

American aircraft carried out 212 strikes last month but launched 751 weapons – an average of 3.5 weapons dropped per strike. In August, an average of just over one weapon was dropped per strike. 

The US military uses various metrics to measure the intensity of its air operations, of which weapons released is one. It is not exactly the same as air strikes, as multiple weapons can be released in a single strike.

The US Air Force said that more B-52 bomber missions had taken place in Afghanistan in September, likely explaining the high number of weapons dropped compared to strikes. These strategic bombers can carry more than 30 tonnes of the widest array of weapons in the US inventory, dropping multiple munitions at a time. 

Resolute Support, the Nato mission in Afghanistan, counts the "desired effect on target" as one strike regardless of the number of pieces of ordnance dropped. This would mean multiple bombs dropped by B-52s on one target would count as a single strike. 

The number of strikes in September was lower than the past five months. However, the high number of weapons released shows the intensity of air operations has not slowed. 

Photo: A B-52H Stratofortress drops a load of M-117 750-pound bombs during a training run (US Air Force)