NEW DELHI, April 27 (AP) —Some Pakistani soldiers who have been fighting separatists in East Pakistan reportedly crossed into India today and exchanged fire with Indian security forces.

Official sources in Calcutta said the soldiers raided a village on the Indian side of the border with East Pakistan at about 3:30 A.M., killed five per sons, injured many others and set fire to several homes. The village is about 65 miles north east of Calcutta.

[Indian military sources said, according to United Press International, that the Pakistani soldiers were pursuing East Pakistani guerrillas across the border and that they executed five Indians who refused to tell them where the guerrillas had fled.]

About five hours later, the informants added, the Pakistani troops came back to within 300 yards of the border and fired toward the Indian checkpost at Haridaspur, which many East Pakistani refugees have used to enter India in the last month.

These incidents, in which Indian border forces were said to have forced the Pakistanis to retreat by returning tire, were reported in the midst of a series of diplomatic charges and countercharges between the two countries.

Accusations Are Exchanged

In the month since the beginning of the military action in East Pakistan on March 25, India and Pakistan have also accused each other's forces of firing across the border and of staging raids. Each has denied the other's charges. Pakistan has also repeatedly accused India of sending infiltrators into East Pakistan to assist the separatists, and India has denied doing so.

In other developments today; press reports reaching Calcutta said 25 Indians were killed in a Pakistani attack on an Indian enclave on the East Pakistani border near Cooch Behar, about 275 miles northeast of Calcutta.

The reports said the Pakistani troops, moving out from the Julaghat area, burned a number of houses in the enclave, called Bashpachai.

Indian news agencies also said Pakistani troops attacked Indian outposts along the east ern border of East Pakistan next to India's Tripura State.

United News of India said the Pakistan Air Force had fired rockets that landed only 100 yards short of the India border near Agartala, the capital of Tripura.

The Pakistani Government, in a radio broadcast, said its troops had wiped out 300 Indian “infiltrators” and their collaborators Sunday in the Sylhet district in northeast East Pakistan.

The radio said two Indian infiltrators belonging to the border security force were captured, along with a huge quantity of arms, ammunition and food stocks.

The Indian Foreign Ministry denied the charge.