(CNN) -- Rangers and scientists have made contact for the first time in more than a year with critically endangered gorillas threatened by a war in the Democratic Republic of Congo, a national park announced Tuesday.
Young gorillas play in Congo's Virunga National Park in an undated photograph.
The Congolese government and rebels agreed to allow the survey team into the gorilla section of Virunga National Park, which rebel fighters loyal to Laurent Nkunda have controlled since September 2007.
Only about 200 mountain gorillas were estimated to be living in the park at last count, out of an estimated 700 in the world.
The team of rangers beginning a planned monthlong survey spotted a group of gorillas Tuesday known as the Humba family group. The Humba group had nine members at last count, said Pierre Peron of Virunga National Park, and experts are eager to see how many it now includes.
Hundreds of rangers had fled the fighting between Nkunda's ethnic Tutsi rebels and the Congolese army and allied militias, leaving scientists with no reliable information about the endangered gorillas. Take a closer look at the animals »
But more than 100 rangers have returned, park spokeswoman Samantha Newport told CNN last week.
At least nine mountain gorillas are known to have been killed last year, including an infant female.
Before the rebels took control of the park, 72 of the gorillas were accustomed to human contact. Another 130 or so were not, making it impossible to accurately count them.
The gorilla sector of the park lies in a strategically crucial area near the border of Uganda and Rwanda.
The U.N. Educational, Scientific and Cultural Organization has designated Virunga National Park as a "world heritage site." Africa's oldest national park, it was formerly known as Albert National Park.
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