The Roman Catholic hierarchy here yesterday reiterated its support for the coming elections, saying for the first time that particular leftist groups trying to stop the vote are responsible for El Salvador's rising level of violence.

It appeared to be a significant change for the four-member Conference of Bishops, which has previously condemned the violence by the left and the right without naming any organization. In their formal declaration, the bishops agreed that Salvadorans reject violence by either side as well as "abuses by elements of the Army and the security forces," adding that world powers are helping to keep the conflict going.

"The present conflict, degenerated into terrorism, has been accentuated recently in various zones of the country by armed communist groups in order to stop the elections," the statement said, referring to the Farabundo Marti National Liberation Front, a coalition of guerrilla organizations. "The international media have maximized and distorted these events, creating a false image of what is happening in the country."

The statement continued that the elections are a peaceful way for "the majority of the people that has said NO to the violence" to express its will and that the vote could be "the beginning of a solution to the armed conflict."

The front has denounced the March 28 legislative elections as a fraud and called on Salvadorans to deface their ballots as a sign of opposition to the governing civilian junta and the military forces behind it. Terrorist groups have been burning and bombing town-hall civil registries for the past month as a way to keep people from voting in their home towns as required.

Acting Archbishop Arturo Rivera y Damas had also been criticizing the elections as useless until last Jan. 22, when he joined in a formal statement by the conference endorsing them. Church sources said Rivera y Damas had received strong pressure from the government, the papal nuncio here and, indirectly, from U.S. Embassy personnel to support the vote that they all view as their only hope to legitimize the government.