British warships are carrying out "high risk" maneuvers within range of Argentine planes and weapons to tighten their blockade around the Falkland Islands, it was disclosed today.

British reporters aboard the Royal Navy task force sent to the South Atlantic to recapture the Falklands from Argentine occupation said warships have sailed through the narrow sound separating the east and west islands as well as around the entire archipelago seeking to locate or engage Argentine forces.

The Defense Ministry announced that early this morning a task force ship shelled an Argentine vessel in the middle of the sound, causing an explosion. The ministry communique said it was not known if the ship, believed to be carrying fuel, was hit or sunk, but a ministry source said it was likely that "the blinding flash was the ship blowing up."

In Parliament, meanwhile, British press coverage of the war came under criticism, with Prime Minister Margaret Thatcher voicing "deep concern" about the coverage by the British Broadcasting Corp.

Reporters on the aircraft carrier HMS Hermes, flagship of the task force, said in censored reports that a frigate had sailed around the Falklands close to shore, fired its guns, sent up a helicopter and put up flares in an effort to locate and engage Argentine forces that seized the islands 39 days ago. The ship was not challenged, they reported.

That maneuver, along with reports that more task force ships have penetrated the sound, indicated that Britain was trying to cut any supply route between the two islands and perhaps isolate lightly defended West Falkland as a prelude to a possible invasion.

The maneuvers also demonstrate that Britain is taking calculated risks with some task force ships by putting them within easy range of Argentine warplanes based on the mainland and also from any shore-based weapons along the sound, much of which is only about 25 miles wide.

Until now it was believed that the task force surface ships were mainly remaining northeast of the Falklands to stay out of range of Argentine planes.

In a noisy debate in the House of Commons, dominated by the criticism of press coverage, Thatcher said "the negotiation will take a little time." She added, however, "the fact that we are negotiating does not close off any military options at all."

Thatcher supported the critics of the BBC, Britain's publicly funded but autonomous radio and television service, leading to heated debate on both sides of Parliament.

She voiced her "deep concern" about the BBC's coverage of the war, adding, "I know how very, very strongly many people feel that the case for our country is not being put with sufficient vigor on certain of the programs--I do not say all--but certain of the programs of the BBC."

Noting that BBC Chairman George Howard had said the network could not be neutral between Britain and Argentina, she added, "I hope his words will be heeded by the many who have responsibilities for standing up for our task force, for our boys, for our people and the cause of democracy."

The Associated Press reported that BBC radio managing director Richard Francis defended the network, saying: "The BBC needs no lesson in patriotism from the present British Conservative government." Speaking at a meeting of the International Press Institute in Madrid, he referred to criticism of a BBC news show that aired film of a distraught Argentine widow at the funeral of her husband.

"The widow of Portsmouth (England) is no different from the widow of Buenos Aires," Francis said. He told delegates at the meeting on press-government relations in a free society: "It's not the BBC's role to boost British troops' morale or to rally British people to the flag."

BBC Assistant Director-General Alan Protheroe said in London: "What we are about is not propaganda but information."

Sir Bernard Braine, a right-wing Conservative caused outcries across the house when he said media presentation of the "defeatist views" of some members of the left who oppose Thatcher's actions in the Falklands was "a sort of treachery."

Opposition Labor Party leader Michael Foot defended the BBC, saying "people are trying to do their duty in difficult circumstances." In turn he called on Thatcher to reprove "the hysterical blood lust" of some of the right-wing papers which support her, saying they "bring such disgrace on the journalism of this country."

In other developments tonight there were reports that the Falklands conflict could lead to the cancellation of Pope John Paul's scheduled visit to Britain at the end of the month and also to a British pullout from the World Cup soccer competition starting next month in Spain.

Cardinal Basil Hume, the leading Catholic prelate in Britain, returned from talks in Rome with the pope and told reporters that "military hostilities would have to cease or be on the way to coming to an end by the middle of next week" if the visit was to go ahead. He said the pope would not come if the situation remained as it is today.

"The key issue is that we should not be sinking each other's ships or killing each other's soldiers," the cardinal said, adding, "the main argument of the holy father is that if the countries are at war, then the atmosphere is wrong for a personal visit."

The visit to Britain, which broke with the Catholic church in the 16th century, would be of historic significance. About 10 percent of Britain's population is Catholic, compared with 80 percent in Argentina.

On the World Cup, British Sports Minister Neil MacFarlane said there was "a question mark over Britain's participation" because of "concern about taking part in a tournament with an aggressor nation."

Argentina is the defending champion in the 16-team tournament which is held every four years and is the premier event in the soccer world. Britain has three teams entered, representing England, Scotland and Northern Ireland.

Thatcher met with her key Falklands advisers and then with the entire Cabinet for three hours this morning in talks that concentrated on diplomatic, rather than military, options, according to sources in the prime minister's office.

Although there was no deadline for the U.N. talks, he said, "things cannot go on indefinitely." He added, howwever, that it would be "unsubtle" for Britain to launch major military moves immediately after any failure in the talks.

There were no reports of further action in the South Atlantic today after the shelling of the ship in the sound. The weather was deteriorating with high winds and full cloud cover, the Defense Ministry spokesman said.