The French government on Tuesday appealed for calm after jailed Corsican nationalist Yvan Colonna died in Marseille a day after falling into a coma following an attack by another prisoner.

The attack on Colonna in early March by a suspected Islamic extremist in a prison in the southern French city of Arles had already triggered violent protests on the Mediterranean island, which has a strong separatist movement.

The government is eager to prevent any further violence, particularly considering France's presidential election, due to take place in a few weeks' time. To this end, the French judiciary on March 17 suspended Colonna's prison sentence for murder on medical grounds following the attack.

The news of Colonna's death has so far prompted two peaceful gatherings in Corsican towns, local media reported.

What has the government said?

"The dramatic circumstances in which [Colonna] was killed are clearly very shocking," said French government spokesman Gabriel Attal said in an interview with Europe 1 radio. "It's necessary now to call for calm and for dialogue."

"Everything will be done to shed light on events which led to this unacceptable situation," he added.

French prosecutors have launched a terrorism investigation over the attack on Colonna. 

Amid the protests in early March, French Interior Minister Gerald Darmanin paid an emergency visit to the island and said Paris might discuss Corsican autonomy.  

In a newspaper interview last week, he reiterated that the government could be prepared to offer Corsica autonomous status.

President Emmanuel Macron has said the issue should not be "taboo" subject but warned that unrest must end before a discussion could begin. 

Why was Colonna in jail?

Colonna, 61, was serving a life sentence for the 1998 murder of the prefect of Corsica at the time, Claude Erignac, who represented the power of the French state on the island.

His capture in Corsican mountains in June 2003 came after the biggest manhunt in French history.  

Some in Corsica still see Colonna, a former goat herder, as a hero in the island's fight for independence, which has seen numerous acts of violence, including some targeting tourist infrastructure.

Colonna was suspected of having taken part in a number of such acts of violence.

tj/wmr (Reuters, AFP)