Lebanese President Michel Aoun vowed that those who were responsible for the violence that erupted on Thursday in Beirut will be held accountable.

In a televised speech after shootings that killed six people, Aoun said it was "unacceptable that weapons are once more the means of communication among Lebanese rivals".

"I have made contacts with the relevant parties today to address what happened and most importantly, to make sure that it never happens again.

"We will not allow anyone to take the country hostage to their own interests."

Six Shi'ites were shot dead in Beirut, in an attack on supporters of Hezbollah and its ally the Amal movement, who were gathering to demand the removal of the judge investigating the explosion that ripped through the city's port last year. It was he deadliest civil violence in Beirut since 2008.

(Reporting by Lilian Wagdy and Ahmed Tolba; Editing by Andrew Heavens and Frances Kerry)