BAGHDAD -- Iraq's envoy to the UN on Tuesday threatened to arrest US troops in the country for carrying out airstrikes on Iranian-backed Iraqi militias in the country amid rising tensions between US troops and pro-Iranian groups. The US "perpetrators will be arrested and held accountable" for the attacks on the Iraqi militias last week, said Iraq's Permanent Representative to the United Nations Mohammed Hussein Bahr Al-Uloom in a draft letter seen by Al Arabiya English. Iran supports militias in Iraq operating under the umbrella of the Popular Mobilization Units (PMU). The US has designated some of the PMU militias, including Katai'b Hezbollah, as terrorist organizations and increasingly come into conflict with them as the US and Iran compete for influence in Iraq. Last week saw an increase in rockets hitting Iraqi bases hosting foreign forces including US troops, with three coalition troops killed on March 11 in an attack on the Taji air base. The same base was hit again on March 14. In response, the US has struck militia groups it accuses of being responsible for the attacks with airstrikes. The Iraqi military said the US airstrikes last Friday had killed six people and described them as a violation of sovereignty. The United States said it carried out the strikes last Thursday against Katai'b Hezbollah, who it blames for a rocket attack a day earlier which killed two American soldiers and a British soldier. "Hostile action against Iraq, the state, its government, people, is a flagrant violation of the conditions for the presence of US forces in Iraq. It is a dangerous escalation intended to make Iraq a place for regional conflicts and agendas. The Government of Iraq expresses its condemnation, and in the strongest possible terms, of those barbaric American attacks that violate the sovereignty of Iraq," the draft letter by Al-Uloom read. "Striking Iraqi military bases, including the Taji camp, is an act of aggression, and measures will be taken, and the perpetrators will be arrested, held accountable as the security of Iraq cannot be tampered with," Al-Uloom threatened in the letter. On top of US-Iran tensions, Iraq has been struck by a wave of ongoing anti-government protests since October. Many of the protesters have criticized the Iraqi government, including Al-Uloom, accusing them of not representing Iraq and having close ties to Iran. Iraqi protesters this past December launched a campaign on social media under the hashtag "Mohammed Hussein Bahr Al-Uloom does not represent Iraq," after Al-Uloom spoke at a UN Security Council session. Activists accuse him of providing misleading information on the Iraqi protests' death toll and those behind the crackdown on demonstrators. During his address to the UN at the time, Al-Uloom said over 300 protesters had died during the mass uprisings by December. Local Iraqi media reports put that number at a much higher 1,500. Members of parliament have accused Al-Uloom and his family members of having ties to Iran. Faiq Al-Sheikh, an Iraqi MP since 2014, tweeted that Al-Uloom's brother, Ibrahim Mohammad Bahr Al-Uloom, had been slain Iranian top commander Qassem Soleimani's top pick to become Iraq's premier. "Ibrahim Bahr Al-Ulum, Qassem Soleimani's candidate for prime minister, is the older brother of Mohammad Hussein Bahr Al-Ulum, our ambassador to the United Nations! The ambassador defended the government of Abdel-Mahdi and insulted the demonstrators, and Abdel-Mahdi has nothing to do with him. Imagine if his brother became prime minister?!," Al-Sheikh tweeted at the time. Al-Uloom is also the son of Mohammad Bahr Al-Uloom, a Shiite religious leader and politician in Iraq. ‐‐ Al Arabiya English