Police in Dallas used a bomb disposal robot to kill a suspect after last night’s deadly shooting during a protest. In a press conference, Dallas police chief David Brown said that the robot was deployed after negotiations with the suspect failed. "We saw no other option but to use our bomb robot and place a device on its extension for it to detonate where the suspect was," said Brown. "Other options would have exposed our officers to great danger. The suspect is deceased as a result of detonating the bomb."

It’s not entirely clear what the "device" in question was, although it may have been one of the small explosives that are normally used to safely detonate larger bombs. A previous statement, from Dallas’ mayor, said only that the suspect had died after police used explosives to "blast him out."

Police have used remote-controlled bomb disposal robots for other purposes; San Jose police talked a man out of suicide last year after delivering a phone and pizza to him via one. But this is the first known case where a department has described using one as a weapon, defense technology expert Peter Singer posted on Twitter, although he notes it's been used this way informally by US troops and insurgents. Unlike with the "killer robots" that have ethicists most worried, any decisions in Dallas were made clearly by humans — it’s much more like an advanced tool used in an unexpected way than anything artificially intelligent or designed for murder. Still, beyond the unmanned drones used in bombing strikes, it’s one of the first known times that a robot has been intentionally used to kill a human outside the battlefield.