Nigeria, July 5 -- President Muhammadu Buhari has condemned a Boko Haram attack on a United Nations (UN) helicopter in Borno State.

The attack occurred when Boko Haram fighters attacked Damasak on Thursday, causing the death of two civilians including a 5-year-old, the UN said on Saturday.

The pilots were, however, able to fly the helicopter back to Maiduguri, about 150km away.

"A UN Humanitarian Air Service helicopter was hit by bullets during the attack. No aid workers were on board at the time and crew members are all safe," the UN humanitarian coordinator in Nigeria Edward Kallon, said in a statement.

"This latest cowardly attack on the UN humanitarian helicopter is yet another desperate rear guard action by the Boko Haram terrori...