Maputo — Portuguese Prime Minister Antonio Costa on Friday apologised for one of the most notorious massacres committed by the Portuguese armed forces during the colonial war in Mozambique.

This was the massacre at Wiriamu and nearby villages in the western province of Tete in December 1972, when around 400 villagers were slaughtered.

Speaking in Maputo, on the final day of his official visit to Mozambique, Costa said "almost 50 years have passed since that terrible day of 16 December 1972, and I cannot but bow down in memory of the victims of the massacre".

He described the massacre as "an unforgiveable act which dishonours our history". He believed that part of today's friendly relations between Portugal and Mozambique must consist of never forgetting the past.

The massacre came to light in July 1973, when the British newspaper "The Times" published a report by a Catholic priest, Adrian Hastings, who told of how soldiers of the colonial army's Sixth Commando company had rampaged through the villages of Wiriamu, Chawola and Juwau, killing about 400 people.

The Portuguese regime and the official Catholic Church counter-attacked. The Archbishop of the city then called Lourenco Marques ranted about "Marxist priests", and tame journalists claimed they couldn't find Wiriamu on the maps (like most African villages, in fact). But Hastings and fellow members of the White Fathers order were credible, and eye-witnesses could be located.

Some of them were still alive when the independent daily "O Pais" visited Wiriamu in 2014 and interviewed survivors of the massacre.

One survivor recalled "they began to burn the houses. Then they said 'you are supporting Frelimo in its fight against the Portuguese troops. So as from today, none of you will live. You will all die'. Then they began to kill the men, and later the women".

Costa's apology was the first time that any Portuguese government recognized officially that the massacre had taken place.