Nigeria says it has grounded its second-largest air carrier over financial concerns.

Aviation ministry spokesman Joe Obi told The Associated Press on Friday that the Nigerian Civil Aviation Authority is auditing Air Nigeria's finances.

The aviation regulator grounded the airline for a day last week for safety checks following a strike by its engineers.

Obi said there are concerns over the payment of the airline staff's salaries.

Air Nigeria said in a statement that the "temporary suspension" only affects domestic and West African flights. It said it would continue flying to London.

Nigeria's aviation industry has come under increased scrutiny after a June 3 Dana Air flight crashed in Lagos, killing all 153 people on board and others on the ground. The crash remains under investigation.