iStock/Thinkstock(NEW YORK) —  The death toll continues to rise from Tuesday’s airstrike on a refugee camp in northeast Nigeria, which the country has called a “regrettable operational mistake.”

The International Red Cross and Red Crescent Movement said at least six of its volunteers were among those killed and 13 others were wounded, though the global humanitarian network said both figures may rise in the coming hours and days. In addition to its aid staff, the International Red Cross and Red Crescent Movement said an estimated 70 others were killed and over 100 were injured.

The Red Cross volunteers were in the remote town of Rann in Nigeria’s Borno state, near the border with Cameroon, as part of a humanitarian operation bringing food to more than 25,000 displaced people when the airstrike hit.

“We are deeply saddened by the loss of our six colleagues and shocked that an incident of this magnitude has occurred in a civilian area,” Bolaji Akpan Anani, president of the Nigerian Red Cross Society, said in a statement today.

The International Red Cross and Red Crescent Movement said its team in Rann has triaged around 100 patients, while nine in critical condition were evacuated by helicopter to Maiduguri, the capital of Borno state, Tuesday. About 90 patients remain in Rann, out of whom 46 are severely wounded and also need to be evacuated, the humanitarian network said.

“The conditions for post-operative care are not adequate, so all the patients must be evacuated to Maiduguri as soon as possible,” Dr. Laurent Singa, a surgeon with the International Committee of the Red Cross in Rann, said in a statement.

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