Sunni Muslim-ruled Gulf Arab states are often wary of subversion from their powerful Shi'ite neighbour Iran, but Dubai's veteran police chief reserves most of his wrath for the "dictators" of the Muslim Brotherhood.
Dhahi Khalfan's suspicions focus mostly on the Egyptian branch of the Sunni Islamist organisation, propelled to power in the most populous Arab country in elections since the overthrow of President Hosni Mubarak in a popular uprising in 2011.
"The Brotherhood as a ruling party in Egypt has no right to interfere with other countries. They are no longer a political party and should respect the independence of other countries," Khalfan told Reuters in an interview this week.
He reiterated charges that Egypt's Muslim Brotherhood was linked to an alleged plot to topple the UAE government, saying the group's ultimate goal was Islamist rule in all Gulf states.
Khalfan, who has often railed against the Brotherhood on his Twitter account, is one of only a few UAE officials to speak publicly about politics.
While he says his tweets are personal views, diplomats say they reflect concerns among the UAE ruling elite about the regional popularity of Islamists and the possibility that the West will engage with them.
Khalfan complained that the West "sympathises, adopts and supports" the Brotherhood, saying he did not understand why.
His stance testifies to new tensions in the Arab world arising from two years of popular ferment that has unseated autocrats in Tunisia, Egypt, Libya and Yemen, although it has so far spared U.S.-allied dynasties in the Gulf and elsewhere.
Khalfan, one of the Gulf's longest serving security officials, defended a trial of the 94 alleged Emirati plotters that human rights groups have criticised as unfair.
"These are dictators," he said of the Brotherhood, which is banned in the UAE, a wealthy, politically stable federation of seven emirates including free-wheeling global trade hub Dubai.
"They want to change regimes that have been ruling for a long time, but they also want to rule forever... We have evidence this group was planning to overthrow rulers in the Gulf region."
He said the defendants, who include lawyers, teachers, judges and a member of the ruling family of one of the emirates, had reached an advanced stage in their alleged conspiracy.
Foreign reporters and international human rights groups have not been allowed to attend the trial that began on March 4.
UAE newspapers have said the defendants belong to al-Islah, a local Islamist group. Al-Islah says it wants peaceful reforms and has no direct links to Egypt's Muslim Brotherhood, although it acknowledges that its ideology is similar.
"The UAE... acted at the right time to stop the Muslim Brotherhood plan that is being directed by the Murshid," Khalfan said, referring to Egypt's Brotherhood leader Mohamed Badie.
The Brotherhood in Egypt, one of whose members, Mohamed Mursi, was elected head of state in June, rejected Khalfan's accusations that the group was involved in subversion abroad.
"We do not act outside the law in any country. We guard the preservation of the law," Brotherhood spokesman Ahmed Aref said. "He (Khalfan) has no evidence of this, of any conspiracy."
UAE-Egyptian ties have been strained since the fall of Mubarak, an ally of Gulf Arab states and a foe of the Brotherhood, which was founded in Egypt in 1928.
Some UAE Islamists, inspired by the rise of religious groups in Egypt and Tunisia, have stepped up their activities, angering officials in a state where no political opposition is permitted.
Asked to describe threats to the UAE, Khalfan said at least two Emiratis had gone to Syria to fight for rebels trying to depose President Bashar al-Assad, but suggested al Qaeda-style militants were not widely supported in the Emirates.
The main Islamist current in the UAE was the Muslim Brotherhood, he said.
Asked about neighbouring Qatar's close ties to the Brotherhood, Khalfan said the UAE respected the Qatari leadership, even if the two countries had differing views.
On Iran, Khalfan, head of Dubai's police force for three decades, criticised what he called Tehran's interference in the affairs of Gulf Arab states and its threats to close the Straits of Hormuz in its standoff with the United States.
However, his language on Iran was relatively restrained, describing it as a neighbour "that is very hard to please".