The latest evidence provided by human rights groups about the abduction of protesters involved in anti-government demonstrations in Iraq raises fresh questions about Tehran’s role in suppressing the protests.
Reports released earlier this week by two human rights organisations, the Euro-Mediterranean Human Rights Monitor and the Iraqi Warcrimes Documentation Centre, have both claimed that an armed Iraqi militia was responsible for kidnapping at least 300 protesters from Iraq's Tahrir Square during recent anti-government protests and that they are now being held in secret prisons in the city.
And a further report by Human Rights Watch has accused militias linked to the Iraqi government of being complicit in a massacre carried out against protesters on December 6.
The publication of these reports comes amid mounting concern about the influence Iran is bringing to bear on the Iraqi government to end the protests, as well as its links to the militias responsible for targeting the protesters.
Human Rights Watch officials have been reluctant to blame Iran directly for having ties with the militias, with a spokesman saying only that “unidentified armed forces, apparently in co-operation with Iraqi national and local security forces, carried out a brutal spate of killings in Baghdad’s main protest area”.
Another human rights official commented: “I can’t say for sure who’s doing it but they’re not local.”
But the US has been more explicit, imposing sanctions against a number of individuals said to be involved with militias linked to Iran and issuing a direct warning to Tehran that it would not tolerate Iranian involvement in any attacks against US interests in the region.
Last week, US Secretary of State Mike Pompeo warned there would be a "decisive response" if American interests were harmed in Iraq – an ally of both Iran and the US.
Since October 28, 10 rockets have been fired at areas where US soldiers and diplomats are stationed in Iraq and while no group has claimed responsibility, US officials have blamed Iranian-backed paramilitary groups.
The attacks prompted US Defence Secretary Mark Esper to express his concerns directly to Iraq’s outgoing prime minister, Adel Abdul Mahdi, reminding him that the US has “a right to self defence” and that it was in Iraq’s interests to stop the attacks “because it is not good for anybody”.
American intelligence officials believe Iran has mobilised its network of agents in Iraq to make sure the protesters do not succeed in their quest for wholesale changes in the way the country is run.
There are now concerns that Iran will try to use its influence to determine the formation of the next Iraqi government after Mr Abdel Mahdi was forced to resign over corruption claims.
American officials are particularly concerned about the activities of Qassem Suleimani, the head of the Islamic Revolutionary Guard Corps’ Quds Force.
David Schenker, US assistant secretary of state, recently warned: “Qassem Suleimani is in Baghdad working this issue. It seems to us that foreign terrorist leaders or military leaders should not be meeting with Iraqi political leaders to determine the next premier of Iraq."
The warning follows recent revelations about the true extent of Iran’s infiltration of the Iraqi government in recent years. Leaked Iranian intelligence documents, written mainly in 2014 and 2015 and published earlier this year, provided damning evidence of Iran’s attempts to embed itself in Iraq affairs, to the extent that it paid Iraqi agents who had previously been working for the US to switch sides.
The revelations prompted a senior Iraqi official to confirm to The National: "Everyone knows that there is a shadow government run by Qassem Suleimani that has infiltrated the political, economic and security sectors of the Iraqi state."
Iran’s attempts to exercise its influence over the Iraqi government is said to be one of the main driving forces behind the recent wave of protests that have swept the country, with demonstrators specifically targeting Iranian diplomatic and military bases in the country.
With the Iranian regime itself under intense pressure from domestic opponents as a result of the impact of US sanctions on the country’s economy, it appears that Tehran is even more determined to make sure that it does not suffer any setbacks in neighbouring Iraq.
This has resulted in an upsurge in Iranian activity in Iraq, which has so far resulted in the deaths of more than 500 Iraqi demonstrators.
Nor is Iraq the only area where Iran forces have intensified their operations. The threat of further Iranian attacks in the Strait of Hormuz has resulted in the US-led naval coalition strengthening its military presence in the region.
Admiral Tony Radakin, the First Sea Lord of Britain’s Royal Navy, criticised Iran’s aggressive and outrageous behaviour in the Gulf, which he said had “not gone away”.
Referring to the seizure of the British-flagged tanker Stena Impero by Iran's IRGC earlier in the summer, Admiral Radakin said Britain would maintain its high military presence in the region for the foreseeable future.
“We have to react when a nation is as aggressive as Iran was,” he said. “It was an outrageous act that happened on the high seas and that’s why we have responded in the way that we have.”
But with the Trump administration showing no desire to ease the pressure on Iran, the expectation among western military commanders is that the IRGC will maintain its aggressive presence in the Middle East in 2020, with all the implications that will have for regional security.
Con Coughlin is the Telegraph’s defence and foreign affairs editor