Armenian Prime Minister Nikol Pashinyan arrives for an interview with AFP in Yerevan on October 6, 2020. (Photo by AFP)

Armenia’s National Security Service (NSS) says it has foiled an attempt by former officials to assassinate the country’s prime minister, Nikol Pashinyan, and to seize power following the recent ceasefire deal with Azerbaijan Republic.

The NSS said its former head Artur Vanetsyan, the former head of the Republican Party parliamentary faction Vahram Baghdasaryan and war volunteer Ashot Minasyan were under arrest.

The suspects were planning to illegally usurp power by murdering the prime minister and there were already potential candidates being discussed to replace him, said the NSS in a statement.

Pashinyan had come under pressure in recent days, with thousands of demonstrators protesting since Tuesday and demanding he step down over a ceasefire that secured territorial advances for Azerbaijan in the disputed region of Nagorno-Karabakh after six weeks of intense fighting.

The ceasefire halted military action in and around Nagorno-Karabakh, an enclave internationally recognized as part of Azerbaijan but populated by ethnic Armenians.

On Saturday, ethnic Armenian villagers in Karabakh set their houses on fire before fleeing to Armenia on the eve of a deadline that will see parts of the territory handed over to Azerbaijan as part of the ceasefire agreement.

Pashinyan said earlier this week he had no choice but to sign the agreement to prevent further territorial losses, calling the situation a catastrophe. He said he was taking personal responsibility for the setbacks, but rejected calls to step down.

Under the agreement, 2,000 Russian peacekeeping troops are being deployed to the region.

The deal was celebrated in Azerbaijan but sparked widespread anger among Armenians, who immediately demanded the pact be invalidated.

Since the early 1990s, ethnic Armenians had held military control over all of Nagorno-Karabakh and substantial swathes of Azeri territory surrounding it. They have now lost much of the enclave itself as well as the surrounding territory.