The Vice Chief of Defence Staff has said that any hint that RAF strikes against Islamic State targets in Iraq and Syria may have caused civilian casualties are rigorously investigated.
On Monday Defence Secretary Gavin Williamson confirmed that an individual riding a motorbike into an area being targeted was "unintentionally killed" by an RAF drone strike on March 26.
It marked the first time the Ministry of Defence, in the years since the air campaign to help try to eradicate the terrorist group began, had confirmed a civilian casualty.
General Sir Gordon Messenger said:
"Whenever there is the potential for there being a civilian casualty as a result of a British strike then we will investigate it as rigorously as we possibly can
"Until this point we have not concluded that a British strike has killed a civilian.
"In this case we concluded that it did, and because we committed to make public the fact that when those unfortunate things happen, that is what you saw yesterday."
When asked how many investigations were made General Sir Gordon was unable to give a number, but said in a year between five and 10.
He also said that investigations are not a frequent occurrence as there is a lot of care taken before the decision to launch ordnance.
On Wednesday in a ministerial statement, Mr Williamson described the death as "deeply regrettable", and said the conclusion was reached after "undertaking routine and detailed post-strike analysis of all available evidence".
Three IS fighters, who were driving in the Syrian Euphrates valley at the time, were also killed by the precision Hellfire missile, a statement from the MoD at the time reported.
The attack was carried out by an RAF Reaper drone, which had tracked the trio.
It was one of more than 1,600 air strikes carried out against IS targets by the RAF in Iraq and Syria, Mr Williamson said.