More from the cited article ...

... For years, the UK, which controls a number of territories in the Caribbean where it bases intelligence assets, has helped the US locate vessels suspected of carrying drugs so that the US Coast Guard could interdict them, the sources said. That meant the ships would be stopped, boarded, its crew detained, and drugs seized.

The intelligence was typically sent to Joint Interagency Task Force South, a task force stationed in Florida that includes representatives from a number of partner nations and works to reduce the illicit drug trade.

But shortly after the US began launching lethal strikes against the boats in September, however, the UK grew concerned that the US might use intelligence provided by the British to select targets. ...