ANTANANARIVO (Reuters) - Two people were killed and dozens injured by an explosion during an Independence Day concert in Madagascar's capital late on Sunday, police said.

President Hery Rajaonarimampianina called the blast an "unacceptable terrorist act", when he visited the 72 people wounded in hospital.

Police said the explosive device at the open-air Mahamasina stadium was likely a grenade.

A similar attack on a concert after the inauguration of Rajaonarimampianina in January 2014 killed one child.

(This story has been refiled to remove a stray word in paragraph 3)

(Reporting by Lovasoa Rabary; Writing by Duncan Miriri; Editing by Andrew Heavens)