Salvadoran moderates are stung by rightists

US-backed Christian Democrats are alarmed by what they charge is a rightist purge here of party members from key government posts and a rash of slayings of party activists.

A broadcast Sunday by leftist guerrilla radio claimed antigovernment insurgents overran the town of Perquin, northeast of San Salvador, and repelled several army assaults to recapture it.

Moderate Christian Democrats, who for two years ruled the Central American nation of 4.5 million in a shaky alliance with the military, called a special meeting Sunday amid charges rightists are purging them from key jobs.