CALCUTTA, India, April 1— Workers dig tunnels under main roads at night so they will collapse when soldiers in trucks move down them. Children in trees and women hid den along roadways serve as lookouts and spies. Girls whittle pointed sticks for pits where soldiers might walk. Young men practice ambushes, in many cases with clubs, stones and bows and arrows.

According to reports reaching the Indian side of the border, these, plus massed attacks on garrisons, are the tactics being used by the East Pakistan secession movement against some 75,000 troops sent from West Pakistan to put the insurgents down.

The reports reaching here, which sometimes conflict with one another, are from East Pakistani resistance leaders, some of whom are said to be in India seeking support from villagers along the border, and from Indian newspapermen who have crossed into East Pakistan on several occasions, The reports are open to question because here in the Indian state of West Bengal almost everyone is supporting the drive of the Bengalis of East Pakistan. The Bengalis on both sides of the border have long had more in common with each other than they have had with their respective countries.

Some Indians say a successful bid for independence in East Pakistan — known here as East Bengal — could be the forerunner of a secessionist move by West Bengal. Ties to “Bengali nationalism” are considered stronger than ties to ideologies or religions. Thus, the Communist party here in predominantly Hindu West Bengal is solidly behind political leadership in predominantly Moslem East Pakistan, which is generally inclined toward the Western world.

Reports are clouded by this relationship, but they do provide some clue of the tactics and thinking of those who are battling the soldiers from West Pakistan, who come from a culturally different region that is more than a thousand miles away, with Indian territory intervening.

The West Pakistani soldiers in East Pakistan are strangers and tactics against them appear to, involve mainly surrounding them in their garrisons and supply centers, cutting of out side supply lines, encouraging the soldiers to use up their ammunition, and then assaulting them with overwhelming numbers of lightly armed men.

In an interview yesterday with a local journalist, one resistance fighter was quoted as saying:

“What we are doing against the army of occupation has possibly not been done any where in the world. We are fighting in human waves with almost no weapons and replying to the rockets with only rifles and revolvers.”

He appealed for arms, including rifles, machine guns, mortars and ammunition, saying they would save lives by making human‐wave assaults unnecessary. These appeals have been widely printed in Calcutta newspapers. The alternative to immediate weapons shipments, the East Pakistanis say, is protracted guerrilla war.

Although the East Pakistanis are said here to favor forcing the West Pakistan soldiers out quickly, they are said to be confident that they can win over a longer period, using guerrilla tactics, with the help of an underground arms supply.

The situation for West Pakistani troops is believed here to be untenable in the long run. Unfamiliar with the territory, they would be vulnerable to ambushes if they attempted to move from their garrisons or from large cities.

The terrain in the Ganges delta resembles that of the Mekong delta in South Vietnam. In both places, movement of trucks and other equipment is restricted in the wet season to a few main roads and waterways. The Americans have thousands of helicopters in Vietnam, the West Pakistanis have only a few in East Pakistan.