RAWALPINDI, Pakistan, Dec. 11—Pakistan said today that India had landed a brigade of paratroops north of Dacca. A spokesman described the situation in East Pakistan as “grim.”

Military spokesmen said they had no details about the Indian landing except that it had been in brigade strength— about 2,500 men—50 to 60 miles north of Dacca.

A spokesman asserted that Major East Pakistani towns, including Jessore and Comilla, were still in Pakistani hands but that landing of Indian troops by helicopter and parachute deep within East Pakistan had bypassed main points of Pakistani resistance.

Truce plan Reported

The Pakistani Army in the eastern section is cut off from resupply from the West and for the last four days has been without the protection of an air force. Dacca was under Continuous Indian air attack yesterday, a spokesman said.

[A Government spokesman in Rawalpindi said Sunday that major diplomatic moves, outside the United Nations, were under way to end the war, but he gaye no details, Reuters reported.]

It was learned today that one of the three generals in Pakistan's Army in East Pakistan had proposed a ceasefire to the United Nations under which non‐Bengalis would be evacuated and political autonomy would be conceded by Pakistan.

In West Pakistan, the over‐all military situation remained essentially unchanged, according to the spokesman. The Pakistani Air Force reportedly shot down an Indian helicopter.

The spokesman said the helicopter‐ had been downed just across the Indian border from Pakistan's Sind Province and apparently was not being used as part of an infantry assault on Pakistani territory.

The Pakistani Navy said that one of its submarines had sunk an unidentified Indian frigate last night in the Arabian Sea. The Indian Navy is blockading the port of Karachi on the Arabian sea.

An army spokesman acknowledged that Indian forces might be fighting west of the Meghna River in East Pakistan, but not, as India has said, advancing overland. He said if they were there, they had arrived by helicopter or parachute.

The Meghna River at its closest point is only 15 miles east of Dacca.

A diplomatic spokesman here was asked whether Pakistan's acceptance in principle of a United Nations resolution calling for a cease‐fire would still be in effect if East Pakistan fell.

He replied that Indian victory in the east is still “hypothetical” and that in any case the resolution calls not only for a cease‐fire affecting both East and West Pakistan but for mutual troop withdrawals and steps for the voluntary repatriation of refugees.

Diplomatic sources here disclosed that with East Pakistan expected to fall to Indian forces in a few days, India had ordered the United Nations to terminate its activities in East Pakistan.

[At the United Nations, officials categorically denied reports from Pakistan, that India had required the United Nations to terminate its activities in East Pakistan.]

Since, according to a Pakistani spokesman, Dacca's airport has been smashed beyond repair by Indian bombs, it is unlikely that United Nations employes or other foreign personnel can be evacuated before the Indians take Dacca.

The United Nations men remaining including Paul‐Marc Henry, head of the United Nations relief organization for East Pakistan, would be stranded in East Pakistan with the status, in Indian eyes, of private citizens.

Closes a Channel

The reported Indian move apparently eliminates an important channel of communication by which a cease‐fire might have been arranged.

Mr. Henry was serving as an unofficial intermediary and had been asked by Pakistani officials to convey two Pakistani cease‐fire proposals to Secretary General Thant.

But diplomats here believe at this point that India will accept nothing short of unconditional surrender in East Pakistan.

There is an impression in the diplomatic community based on high‐level discussions that Pakistan's leadership is resigned to the loss of East Pakistan. Diplomats feel that if India were to offer Pakistan safe conduct for her army and for several million non‐Bengali residents of East Pakistan a start toward negotiations might be made.

Pakistan also presumably would demand terms by which she could withdraw with honor from the eastern wing.

In the west, the Karachi port is now effectively blocked and fuel supplies are running low throughout West Pakistan. Filling stations in Pakistan's NorthWest Frontier Province are limiting gasoline sales to one gallon at a time.

Indian bombing of Karachi oil depots has severely reduced supplies and the armed forces are likely to feel the pinch in a few weeks. If tanks trucks and planes are halted the Pakistani Army can hardly continue, although units might well go on fighting on foot and with bayonets.

India, on the other hand, can obtain almost unlimited supplies from her Soviet ally and, in any case, is vastly stronger than Pakistan.

Despite some Pakistani thrusts at Kashmir, Western experts here believe that India is capable of destroying Pakistan's economic potential for decades to come.

Foreign residents in West Pakistan continued to pour out of the country by special flights and over the Khyber Pass into Afghanistan. What started as a trickle has become a full‐scale evacuation.

Pakistan has not accepted the Indian demand for an independent state of Bangla Desh to replace East Pakistan and until this fundamental issue is settled there appears no chance for a cease‐fire. Furthermore, the Soviet Union seems likely to back India at least to that point.

Ambassador Joseph S. Farland of the United States and other Western envoys visit Pakistan's President, Agha Mohammad Yahya Khan, sometimes several times a day. There is urgent diplomatic activity, mostly aimed at obtaining a cease‐fire.

Even if a cease‐fire began now the effects of t lie war would be felt for a long time. Thousands of people in West Pakistan have been displaced by the fighting.

Food supplies are still adequate in most parts of West Pakistan although prices are rising sharply.