300 Illegal Chinese Immigrants Arrested : Smuggling: Boats try to take refugees ashore south of San Francisco. It is third foiled attempt in three weeks.

Two fishing boats allegedly ferrying Chinese immigrants from a mother ship offshore were seized by authorities Wednesday in small Northern California harbors in a widening of the recent wave of coastal smuggling.

The two vessels, carrying nearly 300 refugees, were seized within hours of each other when they attempted to dock more than 60 miles apart at Moss Landing and Princeton, south of San Francisco.

The U.S. Coast Guard had been trailing the two boats for several days and saw them together before they attempted to unload their cargo, a spokeswoman said. The Coast Guard was still searching for the larger ship believed to have carried the immigrants from China.

The smuggling attempt marks the third time in three weeks that boats packed with hundreds of Chinese have tried to unload their passengers along the coast of California.

Attempts to smuggle Chinese immigrants into the United States by boat have soared in the last year, jumping from 20 people caught in 1991 to more than 1,600 captured in the first five months of this year, according to the Coast Guard.

At the Pillar Point Harbor in Princeton, about 25 miles south of San Francisco, the Pelican, a 46-foot fishing boat, pulled into port about 9:30 a.m. and docked at a slip reserved for the Harbor Patrol.

Harbor Master Bob McMahon, alerted to watch for smugglers, was suspicious because the boat had no fishing gear. When he approached, the pilot tried to sail away but rammed into several other boats and jammed his own vessel under the pier. The pilot ran but was quickly captured by local fishermen, witnesses said.

When authorities opened the fish hold, they were met by an overwhelming smell of human waste and found 148 immigrants crammed into every available space, including the engine room, officials said. Through interpreters, the passengers said they had been on the boat for four or five days and had had no food or water the entire time.

“They are all very weak,” McMahon said. “They seemed to be in good spirits. They seemed to realize they were in America and the worst of their trip was over.”

Immigration and Naturalization Service agents took the immigrants and an unknown number of crew members into custody. Because of concerns about tuberculosis, the immigrants were issued surgical masks to wear during processing. Agents wore surgical masks, plastic eyeshades and latex gloves.

In Moss Landing, south of Santa Cruz, the Coast Guard was on hand when the Angel, a 65-foot trawler, docked at 6:45 a.m. The craft was carrying 149 refugees from China, who were held on board until INS agents arrived and took them into custody.

Several of the immigrants said they began their voyage 40 days ago from Fujian province in China.

Coast Guard Lt. James B. Hall told the Associated Press that both fishing vessels left the Moss Landing marina two days ago. “Somewhere, there must have been a larger ship,” said Hall.

Last week, a freighter carrying an estimated 250 Chinese immigrants slipped into San Francisco Bay during the night and unloaded its passengers at the Presidio Army post. Authorities arrested 169 immigrants but an unknown number escaped into San Francisco.

Three weeks ago, the Coast Guard seized a leaking trawler packed with 200 immigrants off the coast of San Diego as the boat sailed into U.S. waters from Mexico. Chinese are also entering the United States via Mexico after being smuggled by ship into Baja California, according to immigration and Mexican officials.

Authorities cannot say how many other vessels have succeeded in unloading their passengers along the California coast, but holding facilities are jammed with the immigrants from China, many of whom are seeking political asylum.

Paddock, a Times staff writer, reported from San Francisco. Edwards, a special correspondent, reported from Princeton.