The Baltimore waterfront, plagued by recent losses in shipping business and a decline in jobs, erupted in violence this morning when a 59-year-old longshoreman was struck and killed by a police car after union pickets tried to storm a freighter being unloaded by nonunion labor.

The accident followed a night of disturbances in which five longshoremen were arrested and two police officers were slightly injured after stones and bottles were thrown at police officers. A sixth longshoreman was arrested today.

Shortly after the accident, gubernatorial candidate Stephen H. Sachs made a previously scheduled address to a mostly management, maritime trade group and called for the creation of a semiautonomous agency to address the problems of the port.

The speech by Sachs was billed as his first position paper of the campaign, and it came as officials of Maryland's maritime industry are growing increasingly concerned about the loss of shipping business to the aggressively marketed Virginia ports of Hampton Roads. Within the last year, three major carriers have shifted their operations south, taking at least 275,000 tons of cargo, $22 million in revenue and several hundred jobs along with them, Sachs said.

That frustration over the loss of jobs climaxed today when Jackson Taylor of 308 Washburn Ave. was accidentally struck by a police car rushing to Pier 7 at Port Covington, according to a police spokesman. At Pier 7, about 20 protesters were trying to board the Cypriot ship Deby while 400 nonunion workers unloaded bags of cement from Poland.

Members of the International Longshoreman's Association had set up an informational picket line to protest the use of nonunion labor by Baltimore Launch and Marine Services Inc. It was the first time nonunion labor had been used to unload a ship at the Port of Baltimore, according to Port Administrator W. Gregory Halpin.

After the accident, the union ceased picketing, the company took the nonunion workers off the job and both sides sat down to negotiate.

Sachs referred to the disturbances after his address at the Propeller Club, in response to a question from the audience. Michael Moss, a salesman for a ship repair company, said, to nods of agreement from many of his listeners, "Being in a support service, I can do nothing if labor isn't reasonable. I think labor has probably been one of the serious downfalls of the port . . . . Is there anything that can be done to make labor more manageable?" Moss suggested legislation barring unions from compelling all workers at a site to join a union.

Sachs, long a favorite of organized labor, opposed such right-to-work laws. "I think there is a role for public officials [in mediating labor-management disputes]," he said, "especially public officials who have the trust of both sides. Beyond that I don't think I want to comment on what is already a very volatile situation."

In his prepared remarks, Sachs had pointed to the loss of more than $20 million in business so far this year from firms that bypassed Baltimore for the port at Norfolk, on Hampton Roads.

Renewed prosperity, he said, depends on freeing the port's operations from "the entanglements of the state bureacracy," specifically budget decisions and procurement and personnel regulations. He said that the Virginia ports had been able to install more modern equipment more quickly, and had spent four times as much as Maryland on advertising last year.

Currently the Maryland Port Adminstration is a state agency under the direction of the secretary of transportation. If elected, Sachs pledged, he would create an independent Maryland port and trade agency.

One port spokesman said that Maryland recently began a $500,000 program to subsidize railroad transportation rates to make cross-country transportation cheaper through the use of Maryland ports. "We're confident we're going to get the cargo back," said the spokesman, Mel Tansill.

But members of the Propeller Club were not so hopeful. "We are really hurting," said Moss. "The volume of ships is down. If there are no ships, we can't repair 'em."