Kuwait says it has uncovered a Hezbollah plot to assassinate "leaders of the state".
The Ministry of Interior said six people had confessed to espionage and terrorist activities, including training in "assassination skills". Five were Kuwaiti citizens.
It said another 14 suspects, inluding Kuwaitis, Lebanese and Iranians, had been identified outside the country.
"The state security apparatus, following precise surveillance and monitoring operations, has thwarted a terrorist plot and dismantled a network," the ministry said.
"The network was planning to carry out assassination operations targeting symbols and leaders of the state, as well as recruiting individuals to undertake these tasks."
The alleged plot is one of the most serious affecting a Gulf state since the Iran war began. Six countries including the UAE and Kuwait had warned earlier on Wednesday of "destabilising acts" by Hezbollah and other pro-Iran sleeper cells.
Hezbollah, a close ally of Iran, is at war with Israel in Lebanon. Kuwait has already arrested more than 10 suspected members of the group since the war began.
Six of the suspects in the latest plot have had their Kuwaiti citizenship revoked. The "fugitive suspects" outside the state include five Kuwaitis, two Iranians and two Lebanese.
The ministry said they had confessed to receiving "advanced military training abroad" from members of Hezbollah. These were said to include "the use of weapons and explosives, surveillance techniques and assassination skills".
The UAE last week announced the dismantling of a “terrorist network” funded and operated by Hezbollah and Iran. It was alleged the network had been operating in the UAE under a commercial cover and tried to destabilise the economy.
Qatar has also arrested members of two alleged cells linked to Iran's Islamic Revolutionary Guard Corps.
A joint statement by the UAE, Kuwait, Saudi Arabia, Qatar, Bahrain and Jordan on Wednesday said their security services were keeping a "watchful eye" on domestic plots.
The six countries "condemn the destabilising acts and activities targeting the security and stability of the region's countries, which are planned by sleeper cells loyal to Iran and terrorist organisations linked to Hezbollah," they said.
