TEHRAN (AFP/Reuters) - Iran said on Monday a shadowy Sunni rebel group reportedly behind a deadly mosque bombing last week has ties with foreign forces based in neighbouring Afghanistan. We consider Rigis network linked with some foreign forces in Afghanistan, Foreign Minister Manouchehr Mottaki told reporters in response to a question about Thursdays attack on a Shia mosque which killed 25 people in the southeastern city of Zahedan. The suicide bombing was reportedly claimed by Jundallah, a Sunni rebel group headed by Abdolmalek Rigi, blamed for much of the unrest in Sistan-Balochestan province and its capital Zahedan. The southeastern province bordering Afghanistan and Pakistan is home to a sizeable Baloch minority who are Sunnis. Mottaki said Iran had obtained evidence proving its allegation. Mottaki told reporters that Iran and Pakistan have joined forces in combating insecurity since Asif Ali Zardari became Pakistani president late last year. A number of rebels detained in Pakistan have been extradited to Iran within this new framework, he said without specifying whether they belonged to Jundallah. Iran has in past repeatedly blamed US and British agents in Iraq and Afghanistan for launching attacks on its border provinces with significant ethnic minority populations. Jalal Sayah, Sistan-Balochestans deputy governor, said last week that those arrested over the Zahedan attack were hired by America and the agents of the arrogance, a term usually used by Iranian officials in reference to the United States. Iran has arrested a number of people it accuses of sowing sectarian discord in southeastern city of Zahedan, a senior commander was quoted as saying on Monday. News of the detentions in the city of Zahedan, where many of Irans minority Sunni Muslims live, came two days after security personnel defused a homemade bomb found on a flight bound for Tehran from a southwestern city, according to Iranian media. Brigadier General Ahmad Reza Radan, deputy commander of Irans security forces, said a number of individuals who intended to create insecurity in Zahedan had been detained. Three men convicted of involvement in the bombing, the deadliest such incident in Iran since its 1980-88 war with Iraq, were executed in public on Saturday in the city. In the past days some people planned to sow discord between Shias and Sunni citizens in the region. Fortunately, with the prompt presence of government officials and religious dignitaries, unrest was prevented, Radan said. Meanwhile, five people were killed in an arson attack in Zahedan on Monday. Five employees of the local subsidiary of financial company Mehr Financial and Credit Institution perished after an arson attack set the building ablaze, the English-language Press TV said. Mehr Financial described itself on its website as a lending society aimed at improving the welfare of people, especially the Basijis, the hardline militia operating under the Revolutionary Guards.