NBC News on Wednesday revised its account of the 2012 kidnapping of its chief foreign correspondent, Richard Engel, saying it was likely that Mr. Engel and his reporting team had been abducted by a Sunni militant group, not forces affiliated with the government of President Bashar al-Assad of Syria.

In a statement posted on the NBC News website Wednesday evening, Mr. Engel said that a review of the episode — prompted by reporting from The New York Times — had led him to conclude that “the group that kidnapped us was Sunni, not Shia.” He also wrote that the abductors had “put on an elaborate ruse to convince us they were Shiite shabiha militiamen.”

Mr. Engel and his team were kidnapped in December 2012 while reporting in Syria. They were held for five days. Just hours after emerging, they appeared on the “Today” show.

“This was a group known as the shabiha, this was the government militia, these are people who are loyal to President Bashar al-Assad,” Mr. Engel said on “Today,” citing information he had gathered from the group. In that and other appearances on NBC, and in a Vanity Fair magazine article, he said that he had been rescued by Sunni rebels. At least two people died during the course of the captivity, he said in some versions of the account.

Interviews by The Times with several dozen people — including many of those involved in the search for NBC’s team, rebel fighters and activists in Syria and current and former NBC News employees — suggested that Mr. Engel’s team was almost certainly taken by a Sunni criminal element affiliated with the Free Syrian Army, the loose alliance of rebels opposed to Mr. Assad.

The group, known as the North Idlib Falcons Brigade, was led by two men, Azzo Qassab and Shukri Ajouj, who had a history of smuggling and other crimes. The kidnapping ended, the people involved in the search said, when the team was freed by another rebel group, Ahrar al-Sham, which had a relationship with Mr. Qassab and Mr. Ajouj.

Mr. Engel and his team underwent a harrowing ordeal, and it is a common tactic for kidnappers in war zones to intentionally mislead hostages as to their identity.

NBC executives were informed of Mr. Ajouj and Mr. Qassab’s possible involvement during and after Mr. Engels’s captivity, according to current and former NBC employees and others who helped search for Mr. Engel, including political activists and security professionals. Still, the network moved quickly to put Mr. Engel on the air with an account blaming Shiite captors and did not present the other possible version of events.