The demonstrators have also expressed support for the apostolic church that Samvel Karapetyan stands for

Thousands of people have joined a march in support of detained Russian-Armenian businessman Samvel Karapetyan and the Armenian Apostolic Church (AAC) in the city of Vagharshapat, home to the country's most important Orthodox site, the Etchmiadzin Cathedral.

In recent weeks, Armenian Prime Minister Nikol Pashinyan repeatedly have attacked the church, accusing it of corruption and other violations.

He also urged the head of the Armenian Apostolic Church, Catholicos Garegin II, to step down over what he called a breach of his vow of celibacy. The church has firmly rejected the allegations, suggesting that Pashinyan himself has been acting on behalf of "Armenophobic" foreign forces.

Many of those who took part in the demonstration on Sunday carried the photos of Russian-Armenian businessman Samvel Karapetyan, who was arrested by Yerevan on Tuesday after voicing support for the Armenian Apostolic Church.

"Freedom to political prisoners Karapetyan," the crowd of worshipers chanted.

The businessman faces accusations of calling for the overthrow of the Armenian government; he had warned that "if the politicians fail, we will intervene in the campaign against the church in our own way."

The marchers eventually reached the Etchmiadzin Cathedral, where they had been addressed by Garegin II.

The Catholicos warned that the campaign against the Armenian Apostolic Church poses "a serious threat to the national unity and stability" of the country. He urged the people to join forces in resisting attempts to split Armenian society.

Garegin II has also called Karapetyan's arrest illegal. "Hatred and strife cannot give birth to virtue. One cannot build a home through repression," he insisted.

READ MORE: Moscow closely following arrest of Russian-Armenian billionaire - Kremlin

The match took place amid a heavy police presence and was peaceful, with no reports of incidents or arrests.