Saturday, President Emmanuel Macron condemned the "inexcusable" deadly massacre by Paris police on a 1961 protest by Algerians whose scale was covered up for decades by French authorities.

Macron told relatives and activists on the 60th anniversary of the bloodshed that "crimes" were committed on the night of Oct. 17, 1961 under the command of the notorious Paris police chief Maurice Papon.

He acknowledged that several dozen protesters had been killed, "their bodies thrown into the River Seine" and paid tribute to the memory of the victims.

The precise number of victims has never been made clear and some activists fear several hundred could have been killed.

Macron "recognised the facts: that the crimes committed that night under Maurice Papon are inexcusable for the Republic", the Elysee said.

"This tragedy was long hushed-up, denied or concealed," it added in a statement.

The rally was called in the final year of France's increasingly violent attempt to retain Algeria as a north African colony, and in the middle of a bombing campaign targeting mainland France by pro-independence militants.

Papon was in the 1980s revealed to have been a collaborator with the occupying Nazis in World War II and complicit in the deportation of Jews. He was convicted of crimes against humanity but later released.

- 'Much further' -

Macron, the first French president to attend a memorial ceremony for those killed, observed a minute of silence in their memory at the Bezons bridge over the Seine on the outskirts of Paris where the protest started.

His comments that crimes were committed went further than predecessor Francois Hollande, who acknowledged in 2012 that the protesting Algerians had been "killed during a bloody repression".

However, as expected, he did not issue a formal apology. He also did not give a public speech, with the Elysee issuing only the written statement.

The president, France's first leader born after the colonial era, has made a priority of historical reconciliation and forging a modern relationship with former colonies.

But Macron, who is expected to seek re-election next year, is wary about provoking a backlash from political opponents.

His far-right electoral opponents, nationalists Marine Le Pen and Eric Zemmour, are outspoken critics of efforts to acknowledge or show repentance for past crimes.

Historian Emmanuel Blanchard told AFP that Macron's comments represented "progress" and had gone "much further" than those made by Hollande in 2012.

But he took issue with the decision to pin responsibility on Papon alone, saying that then prime minister Michel Debre and president Charles de Gaulle had not been held to account over the ensuing cover-up or the fact Papon would remain Paris police chief until 1967.

- 'Looking with lucidity' -

The 1961 protests were called in response to a strict curfew imposed on Algerians to prevent the underground FLN resistance movement from collecting funds following a spate of deadly attacks on French police officers.

Some of the worst violence occurred on the Saint Michel bridge near the Notre-Dame cathedral where witnesses reported seeing police throwing Algerians into the river Seine where an unknown number drowned.

Macron's comments come in the midst of an ongoing diplomatic row between Paris and Algiers fuelled by comments attributed to the president describing the country as ruled by a "political-military system" that had "totally re-written" its history.

A report commissioned by the president from historian Benjamin Stora earlier this year urged a truth commission over the Algerian war but Macron ruled out issuing any official apology.

Another historical commission set up by Macron also found that France had overwhelming responsibilities over the 1994 genocide in Rwanda, in a finding that has led to a certain thawing in ties between Paris and Kigali.

"France is looking at all its history with lucidity and recognises responsibilities that have been clearly established," the Elysee said.