NEW DELHI, June 10.-A senior health ministry official warned today that if proper precautions are not taken the cholera epidemic now rampant among East Pakistani refugees in West Bengal could spread throughout India, Ministry Secretary K. K. Das described the situation along India's border with East Pakistan as serious, and said every one within a five-mile radius of all refugee camps and other known cholera centers was being inoculated against the disease.

He told newsmen that an estimated 5,000 people had died in the epidemic as of 5:30 a.m. yesterday, when the last official reports were received.

Das gave the number of refugees as 5.5 million which is half a million higher than that given to the Indian Parliament earlier today by Deputy Labor and Rehabilitation Minister Balgovind Verma, who said refugees from East Pakistan are continuing to enter India at the rate of 100,000 a day.

The Soviet Red Cross announced in Moscow today that it would send food, vaccine and tents to India for the refugees.

Soviet Prime Minister Alexei Kosygin said in a public address yesterday that Pakistan should take immediate steps to allow the refugees to return home because, in spite of the aid already sent to them, they were in an extremely serious condition.

Asked today to comment on international reaction to the cholera epidemic, Das said 99 per cent of the medical supplies used in fighting it so far had come from Indian sources .

Medical supplies on hand were sufficient for the present, Das said, but "vast quantities of supplies are necessary because time moves on."

In London, a leading British charity organizer said on returning from the refugee camps that the disease seemed to have been contained.

Michael Blackman of Oxfam relief agency said the main danger for the refugees now was the onslaught of the monsoon, which has just started.

According to Reuters the ranks of East Pakistan refugees in West Bengal have been swollen in the past two days by the arrival of many Moslems, including middle class doctors, bank officials and small landowners.

Since mid-May the refugees had been about 90 per cent Hindu, apparently driven out of predominantly Moslem East Pakistan for religious reasons.

The new influx of Moslems suggested to observers in Calcutta an almost complete breakdown of the social structure in Pakistan's eastern wing, although reliable information on the situation there is lacking.

Pakistan martial law authorities issued a general amnesty today to any East Pakistani who fled to India and who wishes to return.

The amnesty was announced by Lt. Gen. Tikka Khan, governor and martial law administrator of East Pakistan. He urged all citizens who left the country or went "underground under the influence of false and malicious propaganda to return home."

The offer was viewed in Karachi as an olive branch to the secession-minded Awami League and its leader, Sheikh Mujibur Rahman, who is in Pakistani custody. The Awami League's refusal to compromise on its demands for autonomy for East Pakistan led to March's bloody uprising and the wholesale exodus to India.