LONDON -- The Reuters news agency says Maria Golovnina, its bureau chief for Afghanistan and Pakistan, has died at the age of 34.

The agency says Golovnina fell unconscious Monday at Reuters' Islamabad bureau. An ambulance took her to Kulsum International Hospital "but medical teams were unable to save her," the company said.

The agency did not disclose the cause of death.

In a statement, Reuters called Golovnina "a superb journalist with a long and varied career."

She joined Reuters in Tokyo in 2001 and worked in London, Singapore, Moscow, Afghanistan and Iraq before being appointed bureau chief for Afghanistan and Pakistan in 2013.