One park ranger was killed and three other people, including the British citizens, were abducted.
The Foreign Office has confirmed that the two Brits have been kidnapped.
A female park ranger was killed trying to protect two British tourists after gunmen ambushed their vehicle in Congo's Virunga National Park.
"The management of the Congolese Institute for the Conservation of Nature wishes to bring to the attention of the resident of Beni and its surroundings that it is forbidden to fell trees in the park", a statement read.
"For the moment the Congolese Institute for Nature Conservation can not communicate much about the incident because the hostages are still in captivity".
"We are in close contact with the authorities of the DR Congo after an incident involving two British nationals and our employees provide support to their families", - said the British foreign office.
A park guard said the driver was injured in the ambush about 6 miles north of Goma.
Armed groups have staged a series of raids to steal resources, particularly charcoal.
There have been a number of killings and kidnappings in recent years.
Virunga National Park, a UNESCO World Heritage Site, is threatened by numerous armed groups in the region, including Ugandan rebels of the Allied Democratic Forces (ADF).
Last month, five rangers and a driver were killed in an ambush in Virunga National Park.
In an interview with National Geographic a year ago, Virunga National Park Director Emmanuel de Merode said three main groups are responsible for the violence in the park. Before taking the tourists, they murdered the park ranger, Rachel Katumwa, 25, who had accompanied them there.