On 4 March 2018, a former Russian agent (who was convicted of high treason but allowed to live in the United Kingdom via a spy swap agreement), Sergei Skripal and his daughter, who was visiting from Moscow, were both poisoned by a Novichok nerve agent in the English city of Salisbury. They survived, and were subsequently released from hospital. In addition, a Wiltshire Police officer, Nick Bailey, was exposed to the substance. He was one of the first to respond to the incident. Twenty-one members of the public received medical treatment following exposure to the nerve agent. Despite this, only Bailey and the Skripals remained in critical conditions. On 11 March 2018, Public Health England issued advice for the other people believed to have been in the Mill pub (the location where the attack is believed to have been carried out) or the nearby Zizzi Restaurant. On 12 March 2018, British Prime Minister Theresa May stated that the substance used was a Novichok nerve agent.