A hospital in England’s Salisbury on Monday discharged the daughter of the former Russian spy who was poisoned in March, allegedly with a nerve agent, the BBC reported. Her father, Sergei Skripal, remains in hospital, but his condition is said to be “improving rapidly”.

Yulia Skripal, 33, was taken to a secure location after being discharged from Salisbury District Hospital. Doctors are likely to issue a statement on Tuesday, Sky News reported.

On March 4, the father and daughter were found unconscious on a park bench outside a shopping centre in Salisbury. A police detective who attended the scene was also taken to hospital after being exposed to the poison, but he was discharged last month.

Yulia Skripal lives in Moscow but had arrived in England to visit her father just a day before the incident.

The poisoning has led to a major diplomatic controversy globally. The United Kingdom accused Moscow of being involved in the incident and expelled 23 Russian diplomats from its territory. Denying the allegation, Russia responded by expelling an equal number of British diplomats.

Later, over two dozen countries, including the United States, members of the European Union, Australia, Canada and New Zealand expelled over 150 Russian diplomats and closed some consulates. Russia continued to deny it was involved and reciprocated to each move in kind, sparking talk of a Cold War-like situation.