NATO forces in Afghanistan Wednesday freed a New York Times reporter held hostage by militants, though his interpreter and a British commando were killed in the operation.

Stephen Farrell, a dual Irish-British citizen, was abducted Saturday while reporting on the aftermath of a controversial NATO air strike in the northern province of Kunduz.

Farrell told the Times that his interpreter, Sultan Munadi, who was kidnapped at the same time, was shot dead during the rescue effort. Farrell said he did not know if the fatal shots were fired by the rescuers or the militants.

The local governor also said two civilians - the owner of the house and his wife - were killed in the operation.

In June, another New York Times reporter, David Rohde, escaped from militants who had held him for seven months in Pakistan and Afghanistan.  

In both cases, the newspaper, and other media outlets, kept quiet about the abductions to protect the journalists' safety.

Farrell, a veteran journalist, was kidnapped once before while reporting in Iraq in 2004.

Meanwhile, NATO Secretary General Anders Fogh Rasmussen expressed concern about growing criticism about the war effort in Afghanistan.

In remarks prepared for a ceremony in the United States Wednesday, Rasmussen acknowledged that security progress has been slow. But he insisted that extremists must not be allowed to operate in Afghanistan.

He also noted the concerns about the legitimacy of the recent election.

Some information for this report was provided by AFP, AP and Reuters.