London, Jul 14 (IANS): Police have found the source of novichok, a nerve agent that killed a British woman earlier this week after she was exposed to it.

Dawn Sturgess, 44, from Durrington, died on July 8 at the Salisbury district hospital, after handling an item contaminated with the Soviet-era poison on June 30. Her partner Charlie Rowley, 45, who was also taken ill after being exposed to the nerve agent, is still hospitalised.

The Metropolitan Police said on Friday that a small bottle discovered in Rowley's home has been identified as the source of the nerve agent.

However, it remains unclear where Rowley found the bottle, or whether it was the same batch of nerve agent that was used to poison former Russian spy Sergei Skripal and his daughter Yulia in March.

Public Health England has advised citizens not to pick up strange items made from glass, metal or plastic.

"If you didn't drop it, then don't pick it up," officials said on Friday.

Neil Basu, the head of UK Counter Terrorism Policing, said there was no guarantee that all of the substance has been found. Search cordons remain in place.

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.

People poisoned with Novichok and other nerve agents essentially die due to secretions -- vomiting, diarrhea and urinary incontinence occur all at once, reports CNN.

Supportive care includes oxygen; anti-seizure medication, atropine, used for some poisoning patients; and pralidoxime chloride, given to inhibit poisoning including by nerve agents.