By Erika Solomon and Lin Noueihed
MANAMA (Reuters) - Bahrain's King Hamad bin Isa Al Khalifa has said a foreign plot against his Gulf Arab kingdom had been foiled and thanked troops brought in from fellow Sunni-ruled neighbors to help quell weeks of unrest.
Hamad's announcement came after a day of tit-for-tat diplomatic expulsions between Bahrain and Shi'ite-ruled Iran.
"An external plot has been fomented for 20 to 30 years until the ground was ripe for subversive designs ... I here announce the failure of the fomented plot," he was quoted as telling troops in a report on state news agency BNA overnight.
Had such a plot succeeded in one Gulf Arab country, Hamad said, it could have spilled into neighboring states.
The ferocity of last week's crackdown, in which Bahrain called in Gulf troops, imposed martial law and drove protesters off the streets, has stunned majority Shi'ites, the main force behind the protests, and angered Tehran.
Iran, which supports Shi'ite groups in Iraq and Lebanon, has complained to the United Nations and asked neighbors to join it in urging Sunni-led Saudi Arabia to withdraw forces from Bahrain.
In a sign of rising tensions between the countries, Bahrain expelled Iran's charge d'affaires on Sunday, accusing him of contacts with some opposition groups, a diplomatic source said.
He left shortly after the Iranian ambassador, asked to leave last week. Iran expelled a Bahraini diplomat in response.
Bahrain has also said previously that it arrested opposition leaders for dealing with foreign countries.
More than 60 percent of Bahrainis are Shi'ites, and most are campaigning for a constitutional monarchy, but calls by hardliners for the overthrow of the monarchy have alarmed Sunnis, who fear the unrest serves Iran, separated from Saudi Arabia and Bahrain by only a short stretch of Gulf waters.
Bahrain complained to Arabsat on Sunday over "abuse and incitement" on Iran's Arabic-language Al Alam television, Hezbollah's Al-Manar and Shi'ite channel Ahlulbayt, which are all carried by the broadcaster, state news agency BNA said.
Bahrain's political crisis has been the subject of a media war between pro-Iranian channels and Bahraini state television. Both have accused each other of incitement.
Bahrain also condemned a protest outside the Saudi consulate in Tehran, after reports on Saturday that some 700 demonstrators broke windows and raised a Bahraini flag over the gate.
An uneasy calm has spread through the city as most Bahrainis begin to return to work and there were fewer checkpoints in the streets, though helicopters still buzz over Shi'ite areas.
Shaking their fists and shouting "Down with Al Khalifa," about 2,000 people joined the fourth funeral procession in as many days on Monday.
Waving black and Bahraini flags, mourners gathered in the Shi'ite village of Buri, to bury 38-year-old father-of-three Abdulrusul Hajair, who went missing in recent days and was found on Sunday, apparently beaten to death.
Bahrain's largest Shi'ite opposition group, Wefaq, said police told Hajair's family on Sunday to collect his body from hospital.
Speaking at a 15-minute protest in front of the United Nations building in Manama on Sunday, a former Wefaq parliament member said almost 100 people had gone missing in the crackdown.
"We don't know anything about them, we've asked hospital and ministry authorities and none of them are telling us anything about them," said Hadi al-Moussawi, one of around 21 former Wefaq MPs carrying Bahraini flags and calling on the UN to help ensure rescue medical services were working in Bahrain.
(Additional reporting by Rania El Gamal; Editing by Matthew Jones)