MANAMA, Bahrain: Hundreds of Bahrainis rallied in Manama to demand a probe into an alleged plot by some figures in Bahrain's government to rig upcoming elections and marginalize the Shiite majority.

Haq organization called the protest, and two of its activists were arrested on the eve of the rally.

The protesters, gathered outside a mosque, chanted slogans demanding the resignation of the government and raised banners calling on authorities to come clean on the so-called "Bandargate" affair.

Thursday, Haq said it had asked UN chief Kofi Annan to set up an inquiry into the alleged plot to rig the November 25 legislative elections to marginalize the Shiite majority of the Gulf country.

"We seek your support in ... forming an international fact-finding committee to scrutinize and expose ... Bandargate," the Haq group wrote in a letter to Annan.

Shiite are 80 percent of the Bahraini population.

The group, which also includes some Sunni opposition figures, was referring to a controversial report by purported British spy Salah al-Bandar.

In the report, he claimed to have uncovered a secret organization operating within the government to "deprive an essential part of the population of this country of their rights" -- an allusion to Bahrain's Shiite majority.

The letter was delivered to the UN office in Manama on Wednesday, Haq said in a statement in Dubai.

Sudanese-born Bandar, who had worked as a consultant in a government department, was expelled from Bahrain in September.