By Jonny Dymond BBC correspondent in Istanbul

Turkey's chief prosecutor has asked the country's constitutional court to close the Justice and Development Party (AK), the group which currently leads opinion polls in Turkey's general election campaign.

The announcement comes as a thunderbolt, just 10 days before Turkey goes to the polls.

The party's leader, Recep Tayyip Erdogan, stepped down from being a founder member of the party last week, but has remained as party chairman.

The AK party has its roots in Islamist political parties which have been banned, but the party says it has no religious agenda.

The party's religious aspect has caused some concern

The country's chief prosecutor, Sabih Kanadoglu, has accused the party - which appears poised to take power - of abusing the law and justice.

Mr Kanadoglu's case is based on the fact that the party leader has been banned from political life.

Because of a speech that was found to have incited religious hatred, Mr Erdogan was barred from parliament and forced to step down.

But he resigned from "founder membership" of the party, not from its leadership.

Symbolic

He is the party's most visible asset - a charismatic politician who has brought the party enormous support.

But the chief prosecutor views the resignation carried out last week as being nothing more than symbolic.

Now he has called on the constitutional court to ban the party to stop Mr Erdogan from campaigning as its leader.

Turkey is entering uncharted legal and political territory.