PANAMA CITY, JUNE 11 -- The government imposed a 10-day state of emergency today following three days of street battles that top military commander Gen. Manuel Antonio Noriega called the worst disturbances here in seven years.

Noriega, widely seen as the real power behind the government, was the target of three days of protests sparked by accusations by his former second in command, Col. Roberto Diaz Herrera, that the general was involved in murder and electoral fraud.

In an interview here today, Noriega said the state of emergency was declared to avert even wider fighting that could have pitted progovernment militants against opposition demonstrators.

In the interview at Panama City's main barracks, Noriega, eager to display his confidence, sought to dispel speculation about his political ambitions by saying he will not be a candidate for president in the 1989 elections. He declined, however, to place a limit on the time he intends to serve as chief commander of the armed forces.

In response to a government order imposing prior censorship on the opposition daily La Prensa, news editor Winston Robles suspended publication indefinitely.

{In Washington, State Department spokeswoman Phyllis Oakley said, "freedom of the media is key if Panamanians are to resolve their political problems in an atmosphere of democracy." She added: "We also support the goal of free and untarnished elections and the full development of an apolitical professional military institution."

{The State Department also advised Americans planning to travel to Panama to delay their trips.}

At least 60 people were arrested and 12 riot policemen were injured in 48 hours of street battles, Noriega said. More than 100 protesters were reported injured. The Christian Democrats, the largest opposition party, said 50 of its members suffered beatings or buckshot wounds.

About 9,500 U.S. servicemen at the U.S. Southern Command, the largest military base in Latin America, were placed on alert and told to stay off the streets.

The body of a U.S. serviceman was discovered this morning in the trunk of a car outside the city, a U.S. military spokesman said. He said U.S. officials believe the shooting death was probably not related to the riots. The spokesman did not release the serviceman's name.

The government, headed by President Eric Arturo Delvalle, announced the suspension of most constitutional rights before dawn today.

Instead of the riot police who were on the streets yesterday equipped with tear gas and rubber clubs, the streets were patrolled today by machine gun-carrying infantrymen, their faces greased with black paint. Noriega said they could shoot, but only on orders from their commanders. Military helicopters buzzed low over downtown avenues.

By Noriega's account, the Cabinet acted after learning that militants of the official government party intended to take to the streets to "respond blow for blow" to the rioters. The general denied, as he often has in the past, that he participated in the civilian government's decision.

A general strike, called by an opposition coalition uniting business and civic groups and the Roman Catholic Church, was broadly effective in commercial districts of the capital.

Most major banks, including Chase Manhattan and the Bank of America, were closed. Panama is a key offshore banking center, whose 121 international banks hold assets valued at $39 billion.

Even in the old city near Noriega's headquarters, most shops were closed. Three blocks from the barracks, as reporters emerged from a midday interview, working-class housewives on their balconies joined a citywide noise-making protest by banging on saucepans.

Noriega warned that his forces would arrest "vandals" in coming days, but he said it will "not be necessary" to arrest politicians.

However, opposition leader Aurelio Barria, president of the Chamber of Commerce, was detained for several hours with another businessman at a military barracks. Police kept Christian Democratic leader Ricardo Arias Calderon under house arrest during the morning.

Arias said the police departed moments before he received a visit from U.S. Ambassador Arthur Davis. In a statement, Arias thanked Davis for helping protect his safety.

Catholic priests keeping a vigil at the posh golf club home of the rebellious Col. Diaz removed all weapons this morning to avoid a shootout. At midafternoon, troops surrounded the house.

The former chief of staff's charges have been wide-ranging, combining some that appear to be true with others viewed as unfounded. But they touched a nerve among Panamanians who have long suspected Noriega was behind fraud in the 1984 presidential vote and the 1985 murder of a widely admired Panamanian, Hugo Spadafora.

A year ago, U.S. intelligence sources leaked information that Noriega was involved in drug and arms trafficking. They also said he had provided intelligence simultaneously to the United States and Cuba. Noriega dismissed the charges as U.S. intervention.

With the economy declining under a $5 billion foreign debt, urban middle-class Panamanians are resentful that Noriega keeps a tight grip on power but allows apparently freewheeling corruption in the Panama Defense Forces that he heads.