More than 300 people have been killed in Punjab since the latest series of violence began in the summer of 1982. Of this figure at least 50 people were slain in clashes o between Sikhs, Hindus and the police during an outbreak of violence in February.

Hindu leaders immediately called for protest strikes Tuesday in the four states neighboring Punjab and also in New Delhi. Reports from Haryana state, where Hindus had attacked Sikhs in retaliation killings in February, said that authorities have placed the police and paramilitary forces on alert to curb any sectarian violence.

Today's killing followed a fresh outburst of violence in Punjab and New Delhi in which at least 12 people died. On Sunday, three women and a child were killed when attackers - suspected to be Sikhs - hurled grenades at a religious meeting of a breakaway Sikh group.

In separate incidents last week, Sikh militants machine-gunned a family of four near the Golden Temple in Amritsar, Sikhdom's holiest shrine, and killed an Indian soldier in a bomb blast. And last Wednesday in New Delhi, terrorists gunned down the moderate leader of a local Sikh organization.

''Those who started the agitation in Punjab should make a major effort to control the forces of terrorism which have been let loose,'' Home Affairs Minister, Prakash Chand Sethi, told Parliament here today. Constitutional Amendment