EAST BERLIN, AUG. 19 -- East Germany's first and last elected government split apart today, exemplifying the country's rapid collapse into West German control.

The Social Democrats, the second largest of four parties in Prime Minister Lothar de Maiziere's ruling coalition, voted by a large majority to pull out of the government to protest de Maiziere's firing last week of four cabinet ministers. He said the four had failed to give hope to East Germans suffering through the country's rapid transition from communism to a market-based economy.

"Because of the behavior of de Maiziere," said Social Democratic Chairman Wolfgang Thierse, the party "has decided to leave this broken coalition."

The collapse of the four-month-old coalition means that de Maiziere loses the two-thirds majority he needed to approve treaties of unification with West Germany. Without such treaties, West German law is expected to be imposed unilaterally on East Germany.

But de Maiziere still has a simple majority, and the coalition's collapse is not expected to effect the scheduled Dec. 2 all-German elections.

The Social Democrats' departure could move up the date of East Germany's disappearance from the map, however. Previously set for Oct. 15, that move -- which requires only a resolution by the East German legislature -- could now come in mid-September. Thierse said today that his party will ask for a vote Wednesday to set unification for about Sept. 15.

Today's action appeared to be largely a matter of positioning for this fall's first all-German elections.

The Social Democrats want voters to perceive them as an opposition party, not as part of the government responsible for the soaring unemployment and closure of industries since the transformation of the East German economy. They want to paint de Maiziere, a Christian Democrat, as too willing to bend to the desires of his party colleague, West German Chancellor Helmut Kohl.

The major East German parties are to be dissolved into their West German partners after unification. The Social Democrats are the major opposition party in the West and are arguing that Kohl moved too swiftly to unify the two economies.

The confusing state of party politics reflects deeper woes in a society in which people live simultaneously with Western economic rules and the remnants of communist controls.

East Germans are buying Western cars even as they lose their jobs. Prices skyrocket to West German levels while East Germans continue to earn low wages that reflect 40 years of Communist subsidies. The soaring unemployment and collapsing industries can only be saved by a complete West German takeover, politicians in both Germanys now say.

De Maiziere blamed the firing of the four ministers on their failure to manage the economy, but his move was widely seen here as little more than a cosmetic attempt to appear an active manager as the government wound down.

Immediate dissolution of the legislature would end the Germanys' attempt to make their reunification an orderly, legal process, marked by treaties covering everything from traffic laws to defense. But East German editorialists wrote today that their legislators are unlikely to give up the perks of office -- many of them have their own offices and cars for the first time in their lives -- before they have to.

A poll by a top West German survey company indicated Friday that only 27 percent of East Germans have confidence in their government, a sharp drop from 56 percent in May.

This weekend, whatever confidence remained was dealt another blow when the East German Defense Ministry revealed that the National People's Army is still training guerillas from the Palestine Liberation Organization at an army base on the Baltic Sea coast.

About 200 Palestinian, Libyan and Yemeni guerrillas were said to be enrolled in the program. The news led to a strong protest from West Germany's small Jewish community, which had been cheered in recent months after the new freely elected East German government said it wanted both to recognize Israel and to pay reparations for German crimes against Jews during the Nazi Third Reich.

East German Disarmament and Defense Minister Rainer Eppelmann said the training could last for "several years" because East Germany was stuck with treaties that the former Communist government had signed. But West German defense officials said East Germany should end the program immediately and that Bonn would not under any condition continue the training after unification.

Eppelmann confirmed that East Germany had been training Iraqi soldiers early this year.

East Germans also learned last week of accusations by the new government that the Stasi, the now-disbanded secret police, killed dozens of dissidents whose deaths had been reported as natural. Among those who may have been killed by the state was Dean Reed, an American-born folk singer and defector who was used as an anti-American propagandist by the Communist regime.

Reed died in 1986 at age 47 in what was alternately reported as a suicide and an accident.