Salvadoran President Jose Napoleon Duarte yesterday blamed the extreme right in his country for violence against journalists, saying some of the violence "could be" coming from within the military.

"There is a structure of the extreme right in this country and they really worry about if we win the elections," he said. "They're doing everything they can and one of the things they are doing is threatening people."

Four Dutch journalists were killed in El Salvador Wednesday, and the government said then that they had been caught in a firefight between guerrillas and the army. Threats against other foreign journalists also were reported last week.

Duarte yesterday predicted a good turnout in next Sunday's controversial constituent assembly elections despite intimidation by extremists of both left and right.

"The people--I believe they are ready to go out and vote," Duarte said on the television interview show "Face the Nation" (CBS, WDVM). The interview was taped Saturday in San Salvador and broadcast yesterday.

Leftist guerrilla leaders have been threatening a major offensive just before the elections, including the destruction of buses and other means of transportation. They have also threatened violence against anyone who votes.

Duarte said he was confident the army would be able to maintain control throughout the week and secure the voting places on election day.

He predicted that at least 500,000 Salvadorans would vote to elect a constituent assembly, which then is expected to draft a constitution.

The election is backed by the U.S. government, which is anxious to bring a democratic process to a country now ruled by a civilian-military junta, but opposed by critics who argue that no plebiscite in the middle of a raging civil war can have any legitimacy.

Duarte responded yesterday to the criticisms by asking: "Is there any other time to vote ? . . . I am asking the people to go out and vote against violence."

He said that right-wing forces have threatened to hang him if they win next Sunday, but said he will not flee the country. "I'll stay and keep on working for democracy and if they hang me, well, that's the price I'll pay for my country."