Israelis fire on parents of injured British peace activist

Mrs Hurndall, a schoolteacher from Tufnell Park, north London, said: "We were passing through the checkpoint very, very slowly when there was the sound of a bullet – it was like the sound of a large stone coming off the car.

"What struck me was the ludicrousness of the situation. Here we were, the parents and brother of someone who has been wounded by Israeli Defence Forces and who then fire a warning shot over our car for no apparent reason.

"It was a measure of the insanity that can take hold here." The single shot was fired from one of two watchtowers that stand above the checkpoint, causing the two British cars, identifiable by their white diplomatic plates, to come to an immediate halt.

Not until the defence attaché, Colonel Tom Fitzalan-Howard, had stepped from the car with his hands in the air to talk with the soldiers inside the tower was the convoy able to proceed.

Notice that the cars would be passing through Abu Khouli was given at least three times – in the days before the trip, just as it was setting off and 10 minutes before it arrived.

A Foreign Office spokeswoman said: "A single warning shot was fired as our staff were crossing the checkpoint. No-one was injured but the incident has been raised with the Israeli Defence Forces."

It is understood that an Israeli Army captain at the checkpoint later told members of the convoy that the shot had been fired because the vehicles had not stopped. There was no order to do so.