Over 20 others were sentenced to up to 10 years in prison by a court in Bahrain, which was hard-hit by Iranian attacks during the war.

Ruled by a Sunni Muslim dynasty, the tiny kingdom has a large Shia population that has long complained of marginalisation.

A woman "accused of... collaborating with the Iranian Revolutionary Guards terrorist organisation, with the intention of carrying out hostile terrorist acts" was sentenced to life imprisonment, the public prosecution said in a statement.

Two other people, one of whom fled to Iran, also received life sentences and a 10,000 dinar fine ($26,487) on similar charges, it added.

In a separate case, "the court sentenced 10 defendants to prison terms of up to 10 years", with three of them to be deported after serving their sentences.

They were convicted for supporting Iran, filming in prohibited locations and disseminating banned statements.

Another 11 people were sentenced to up to five years in jail and a fine for "violence and sabotage committed during the Iranian attacks on the Kingdom of Bahrain last March", the prosecution said.

The sentences come as Gulf countries are on high alert, with Qatar, Kuwait and the United Arab Emirates also cracking down on Iran-linked networks.

Bahraini authorities have arrested more than 300 mostly Shia Muslims since the war began, according to Bahraini activists, some of them accused of espionage or ties to the Revolutionary Guards.

Bahrain has denied cracking down on citizens based on their religious identity.

On May 9, Bahrain's interior ministry said security services had dismantled an organisation accused of links to Iran's Guards and arrested 41 of its suspected members.

On May 7, Bahrain's parliament expelled three MPs who opposed a royal decree abolishing the right of appeal against government decisions on nationality, after 69 people were stripped of citizenship for supporting Iran during the war.