UN on ETHICS of 'killer robots'

The robots are machines programmed in advance to take out people or targets, which - unlike drones - operate autonomously on the battlefield, and now they are being developed by the US, UK and Israel, but have not yet been used.

Supporters say the "lethal autonomous robots", as they are technically known, could save lives, by reducing the number of soldiers on the battlefield.

But human rights groups argue they raise serious moral questions about how we wage war, reports the BBC in Geneva.

They include: Who takes the final decision to kill? Can a robot really distinguish between a military target and civilians?

If there are serious civilian casualties, they ask, who is to be held responsible? After all, a robot cannot be prosecuted for a war crime.