The first of more than 200 schoolgirls missing after being kidnapped by Boko Haram militants from Chibok in northeast Nigeria more than two years ago has been found, a parents' spokesman told the Thomson Reuters Foundation on Wednesday.

Lawan Zannah, secretary of the association of parents of missing Chibok girls, said teenager Amina Ali was found on Tuesday near the Sambisa forest near the border with Cameroon.

The circumstances of her discovery have not yet be officially confirmed.

"She was carrying a baby but I do not know whether it is a boy or girl," Zannah said by phone from Chibok.

Ali was sitting in a military vehicle at the area commander's residence in Chibok, Zannah said. He was not allowed to question her beyond exchanging greetings in their local language, Kibaku, he added.

Zannah said he had first heard of her rescue from Yakubu Nkeki, chairman of the parents association, who had received a call from members of a vigilante group in Chibok saying they had found one of the missing girls.

Boko Haram militants have killed an estimated 15,000 people and kidnapped hundreds of men, women and children in their six-year campaign to carve out a medieval Islamic caliphate in northeast Nigeria.

The kidnapping of the Chibok girls in April 2014 from their school unleashed a wave of international outrage, backed by figures such as U.S. first lady Michelle Obama under the Twitter hashtag #BringBackOurGirls.