The five men - led by Nairi Hunanian, a former journalist and member of the nationalist Dashnaktsoutioun party - had already been charged with terrorism and weakening state power.

The political fallout from the storming of parliament continues - the national security minister has offered his resignation.

The resignation of Sergei Sarkissian - and that of the interior minister, which was submitted earlier - had been demanded by the army.

However, an official spokesman said neither offer had as yet been accepted.

Death sentence possible

If convicted, the five suspects face up to 15 years in prison or the death sentence, though there has been a moratorium on capital punishment in Armenia since 1994.

The attackers released some 40 hostages and surrendered on Thursday after 18 hours in the parliament chamber, when they were allowed to speak on national television and were promised a fair trial.

The gunmen said they had opened fire to punish corrupt officials.

They accused the government of allowing Armenia to disintegrate and claimed the country's elite had sapped the economy through corruption.

Constitutional conundrum

The incident has left a constitutional knot which is apparently preventing parliament from meeting.

President Kocharian will be asked to break the constitutional deadlock

Parliamentary spokeswoman Asmik Khachaturian said the assembly was unable to gather because only the speaker could convene an extraordinary session.

Speaker Karen Demirchian was among the victims of the shootings.

"There will be no session today," Ms Khachaturian said.

"I cannot tell you when it will take place."

Parliament is due to hold a regularly scheduled session next week, but officials are hoping it can meet early to elect a new speaker and two new vice-speakers.

A new prime minister was to be named only after parliamentary leaders were chosen.

A senior official of the Constitutional Court, Armenia's highest authority on constitutional matters, said President Robert Kocharian might have the power to call a special session of parliament to elect a new speaker.

The parliament's co-ordination council has requested President Kocharian to convene an extraordinary sitting of parliament on Tuesday afternoon.