ADEN, Yemen - Military checkpoints are placed on all of Aden's entrances, UAE and Yemeni forces are spread across the city, and several military camps act as its centres of power.

Yet none of this has stopped the assassination of dozens of preachers and supporters of Abd Rabbuh Hadi, the Saudi-backed president - and their colleagues and the wider city want to know why.

The Tuesday assassination of Shawqi Kamadi, an Islah party leader and preacher at al-Thwar mosque, was the latest in dozens of "hits" on Hadi supporters, and many fear it will not be the last.

Preachers fear to speak about support for the president and other political issues, because there are many opponents in Aden

- pro-Hadi preacher

The killing comes after three pro-Hadi military leaders and a preacher were assassinated in the week previous, adding to the 22 pro-government preachers and dozens of pro-Hadi military leaders killed since the middle of 2016. No individual or group has claimed any of the killings.

Such is the situation in Aden. It is the seat of a president who has visited not once since fleeing to Riyadh in 2016 fearing for his life, and where his supporters are picked off one by one.

The city is de facto controlled by the UAE-backed "Security Belt", a militia hostile to Hadi's government and aligned to a secessionist movement lead by a former Aden governor he sacked.

Such a murky political backdrop, as alliances are weaved as quickly as others unravel, has led many to question who controls the hitmen behind the spate of targeted killings.

Cut down in the street

From his minbar (pulpit) almost every Friday, Kamadi would insist on support from the faithful for Hadi. His message was cut off when he was shot dead in the street by a gunman who fled the scene on a motorbike.

Hadi's minister of endowment, D Ahmed Atiya, called on the interior ministry and security forces to intervene to save others from the same fate. Investigations by both have so far produced nothing.

"We call the interior ministry and security forces to save other preachers and Islamic scientists.""Every day we hear about assassination of an imam, preacher or herald," she said on Facebook.

Unknown gunmen have assassinated Shawqi Kamadi in the city of #Aden, A #Yemeni interim Capital. Shawqi Kamadi is a public figure and member of #Islah Party. I am shocked and appalled by this brutal act. I strongly condemn this criminal act. pic.twitter.com/E49sBxT3fH

— Adel Doshela#Yemen (@DoshelaAdel) February 13, 2018

Another pro-Hadi preacher in Aden, who spoke anonymously, said: "Preachers fear to speak about support for the president and other political issues, because there are many opponents in Aden."

He said every preacher assassinated in Aden had been pro-Hadi.

"Some preachers insist to continue in their religious task, talking about sensitive political issues, but I am not going to talk about any political issue because there is no Emirati armoured vehicle protecting me and I am not outside Aden."

He stated that some pro-Hadi preachers faced anonymous threats to stop their public support for Hadi.

The accused

Suspicion, inevitably, has fallen on the "Security Belt" and, by extension, the UAE. The UAE opposes the Islah party, the Yemen branch of the Muslim Brotherhood, and forces from the Belt have burned and looted its Aden headquarters twice.

In January, Belt soldiers routed the presidential guard in a series of battles that stopped only at the gates of the presidential palace. And all the while, the assassins target Hadi and Islah supporters.

The undersecretary of the ministry of information, Abdulraqeeb al-Hudayani, accused the UAE of being behind the targeted killings. Suspects are rarely caught, but those who are end up in Emirati hands, and then disappear.

"Where are the three criminals who were involved in the assassination of Sheikh Abdurrahman al-Adani?" he said of a Salafi leader assassinated in February 2016. "Where are the killers of the former governor of Aden, Jaafar Mohammed Saad?"

Hudayani said suspects were arrested in both cases, sent to prisons controlled by the UAE, and never seen again.

"All of us know the killers and all evidence is in front of us but there is no strong government to stop the chaos in Aden," he said.

Tawakkol Karman, a Noble Peace Prize winner in 2011, said on Facebook: "The UAE supports the assassinations, to make the south its territory, but our population is stronger than them and those crimes will not pass without someone being held to account.

"We will call to account Mohammed bin Zayed and Mohammed bin Salman over all clear and hidden crimes against Yemenis," she said in reference to the leaders of Saudi Arabia and the UAE.

"I stand with the Islah party, Salafis and the all population who were betrayed by their bad neighbours."