(CNN) -- Authorities in Azerbaijan have arrested 22 people they say were spying for Iran and plotting attacks on Israeli and Western targets, the government announced Wednesday.
A statement from the central Asian nation's national security ministry said the group stands accused of spying, treason and "other grave crimes." It did not indicate when the arrests were made.
The spy ring dates back to 1999 and had been supplied with money, military training and weapons, the statement said.
Under the instruction of Iranian handlers, its members "were spying, collecting and delivering information to use against the national security of the Republic of Azerbaijan," the statement said. In addition, it said, they were seeking new recruits.
The Iranians started by recruiting Karimov Niyazi Alovsat while he was on a visit to Tehran in 1999, the statement said.
He was promised large sums of money to find others who would carry out sabotage and terror attacks "against the embassies, representations and organizations of the U.S., Israel and the Western countries in Baku," Azerbaijan's capital, the ministry said.
He and other suspects attended military training camps in Iran, where they mastered weapons and explosives skills, the statement said. They also gathered information in Azerbaijan about potential targets.
Firearms, ammunition and explosives were found when properties connected to the suspects were searched, the ministry said.
No group or individuals linked to Iran have ever carried out an attack against U.S., Western or Israeli targets in Azerbaijan, an oil-rich nation that lies on the Caspian Sea.
Relations between Azerbaijan and Iran, which share a border, have grown increasingly rocky since the government in Baku started building relations with the United States and Israel, supporting sanctions against Iran, and supporting the many Iranian Azeris' calls for an independent state.
Many in Iran are of the view that the Azerbaijan government is in the pocket of the U.S. government because of the economic aid and military support it receives from Washington.
And Wednesday's arrests of suspects with reported ties to Iran are not the first in Azerbaijan.
Baku announced last month that a number of people had been arrested in connection with an alleged Iranian-organized plot against foreign citizens. The National Security Ministry said the plotters had acquired weapons and explosives.
And in January, Azeri authorities arrested two local people allegedly plotting an attack on the Israeli ambassador and a rabbi in the country's small Jewish community. It said they, too, had worked with a criminal figure who had links to Iranian intelligence.
In turn, Iran has furiously accused Azerbaijan of allowing the Mossad, Israel's intelligence agency, to launch terrorist operations across the border.
Israeli and Western counterterrorism officials believe that elements within the Iranian regime most likely sponsored the plots in Azerbaijan, looking for revenge after the killing of several Iranian nuclear scientists.
Iran has strenuously denied involvement, accusing Israel and the United States of trying to provoke conflict.
Azeri Defense Minister Safar Abiyev pledged Tuesday in Tehran not to allow other nations to use Azerbaijan's territory to launch attacks on other countries, particularly Iran, according to the semi-official Fars news agency.
His comments followed a warning from Iranian Deputy Foreign Minister Abbas Araqchi last month against aiding Israel in such attacks, the news agency reported.
CNN's Igor Krotov, Mitra Mobasherat and Reza Sayah contributed to this report.