Polish Communist Party leader Edward Gierek today dismissed the government's top labor negotiator amid indications that pressure is mounting for new leadership to break the deadlock in the strike that has crippled the economy of Poland's Baltic coast.

The first official victim of the turmoil was Deputy Premier Tadeusz Pyka, who was replaced today after being appointed earlier this week to head this government's commission investigating workers' grievances. Officials said Pyka had been assigned to other, unspecified duties.

The government totally reversed its mass-media policy today, speaking openly about the strikes and launching a massive publicity campaign against the reform movement. The party newspaper Trybuna Ludu called for a decisive political confrontation with what it called "people who want to exploit the atmosphere of tension through demagogic political slogans."

"We have been challenged to a fierce political struggle. We have to win it for the well-being of our country," the paper said in a front-page editorial.

Meanwhile, strikes continued to spread, with thousands of workers shutting down dozens more factories today, according to news agencies. United Press International reported that Polish officials were expecting widespread strikes in Warsaw Friday and residents of Warsaw were stocking up on supplies in panic buying this afternoon.

[Polish Premier Edward Babiuch reportedly left today for Gdansk, the heart of the strike action. The Yugoslav news agency Tanjug quoted official Polish sources as saying Babiuch might address the strikers and citizens of the strike-bound region. Pyka's replacement, Mieczyslaw Jagielski, a former agriculture minister and the most powerful of Poland's five deputy premiers, also went to Gdansk, immediately appeared on radio and offered to meet with individual strike committees in their factories.]

The mayor of Szczecin, a port city of 400,000 people on the East German border, reported that "the life of all families is disorganized. Municipal transport is not functioning. Normal functioning of hospitals, shops and fundamental services has been disrupted, and people are still buying food in vast quantities."

Pyka's abrupt dismissal reflected his commission's failure to dent significantly the solidarity of the workers supporting an integrated strike committee with its headquarters in the giant Lenin Shipyard in Gdansk. The government has ruled out all negotiations with the strike committee that has, in turn, forbidden its supporters from negotiating with the commission.

According to Communist Party sources, an emergency meeting of the Communist Party Central Committee is likely to be held in the next few days to seek ways of breaking the impasse. Most speculation surrounds the future of the party secretary, Edward Gierek, who himself came to power in Poland following a similar wave of strikes in December 1970.

Gierek is understood to be resisting some suggestions that he step down in favor of a new leader. Associates reported that he was genuinely shocked earlier this week when strikers failed to obey his televised appeal to return to work.

In advance of personnel changes, the authorities are attempting to regain the initiative by detaining leading dissidents who have operated an information service on the strikes since the present labor unrest began over seven weeks ago.

[Polish police arrested another opposition leader today, bringing the number of detained dissidents to 19. Reuter reported that today's arrest was of Leszek Moculski, leader of the Anticommunist Confederation of Independent Poland.]

After barely mentioning the strikes at first, the officially controlled press is now devoting widespread coverage to them, including reaction from foreign capitals. Particular attention is being paid to the immense economic damage caused by the strike, which is said to be running at $3 million a day in the port of Szczecin alone.

In Gdansk, center of the unrest, the Lenin Shipyard is losing $1 million a day. Seventy ships are waiting to be unloaded and are incurring huge penalty fees. Some smaller ships have left the port without the help of pilots or tugs -- but large tankers with oil for the Gdansk refinery are stuck.

The bottleneck at the ports is also causing serious problems for the economy. Thousands of tons of wool and cotton needed by the textile industry are blocked in Gdansk, as is fodder for cattle and grain. Rail junctions are also blocked and hundreds of wagons of coal cannot be exported.

In the face of mounting economic and political problems, the communist authorities are under just as much pressure as the strikers to act fast. The need for urgency was underlined by Poland's leading journalist, Mieczyslaw Rakowski, in a major article in the influential weekly Polityka that appeared today.

Rakowski wrote that, unless action was taken to restore normal work within the next few days, Poland would face the threat of entering "a period of instability," the consequences of which would be dangerous for everybody. He also hinted at leadership changes by writing that "the question of responsibility for mistakes remains an open one."

Choosing his words carefully, Rakowski added that someone must be to blame for the strikes: "Either the group bearing the main responsibility for the development of our country or the factory crews who have abandoned work." In either case, he wrote, "this indicates that at some point there was a lack of understanding between the leadership and quite a substantial group of the working class."

Rakowski, who occupies a special position in Polish journalism as a member of the ruling Central Committee, argued in favor of the rapid introduction of a broadly based reform program. This may, however, be opposed by more conservative members of the leadership.

It is still by no means clear who would succeed Gierek if he is induced to resign. The reformist faction within the leadership may favor Stefan Olszowski, who was stripped of his Politburo membership at the last party congress in February and exiled as ambassador to Berlin. A former foreign minister, he has both international experience and economic expertise.

Olszowski enjoyed the reputation of being an energetic and pragmatic politician associated with reformist trends. He also has the advantage of being untainted by the mistakes of the past few months because he has been out of power in Poland.

Other possible candidates for the leadership include Jerry Lukuszewicz, a Politburo member in charge of ideological and propaganda work, who might appeal to the more hard-line faction, and Premier Babiuch.