Follow CBSMIAMI.COM: Facebook | Twitter

AMESBURY (CNN) – A bottle discovered in the home of Novichok victim Charlie Rowley has been identified as the source of the nerve agent that killed his partner.

READ MORE: Weekend Forecast: Typical Summer Pattern Continues

It is not clear yet where Rowley found the bottle, or if it is the same batch of nerve agent that poisoned Russian citizens Sergei and Yulia Skripal, London’s Metropolitan Police said.

READ MORE: Tracking The Tropics: Tropical Storm Peter Forms

Earlier this week police opened a murder investigation after Rowley’s partner, Dawn Sturgess, 44, died from exposure to the Soviet-era poison.

MORE NEWS: New Daily Virus Cases In Florida Lowest Since July

Sturgess and Rowley fell ill in the town of Amesbury in Wiltshire, about eight miles north of Salisbury, where the Skripals were poisoned. Yulia Skripal was discharged from the hospital in April and her father was released a few weeks later.