A 45-year-old Associated Press reporter was reported missing today, [WORD ILLEGIBLE] the approximately 35 Argentine journalists who have disappeared over the past four years.

Oscar J. Serrat, a member of the AP bureau here since 1953, reportedly left his home for work in downtown Buenos Aires at 6 a.m. today. AP Bureau chief William Nicholson said Serrat, who normally opens the office in the mornings,never arrived.

Nicholson said he had "no idea" what may have happened to Serrat and said he would "rather not go into" AP queries to the government here over the journalist's whereabouts.

While reports of disappearances of local reporters diminished following a March, 1978 military coup that installed the current Argentine government of Gen. Jorge Rafael Videla, at least four journalists, including Serrat, have vanished since March of this year.

One journalist was found dead in April, and a number of others have been arrested for interrogation about alleged subversive activities, Jacobo Timman, publisher of La Opinion, a leading Buenos Aires daily newspaper, has been imprisoned without charge since last summer.

Government officials have said that Timerman is being investigated for "economic subversion" in connection with business operations involving the [WORD ILLEGIBLE] Argentina's leading terrorist group.

Still missing are Edgardo Sajon, press secretary to former president Alejandro Lanusse, who disappeared last April, and Rofolfo Pondal, assistant editor of a pro-government political journal, who disappeared in July. Rudolfo Walsh, a leftist writer, has not been seen since last spring, when his wife reported that he was abducted from his home.

All of those disappearances are attributed by informed ovservers here to rightist factions within the government. Although none of the missing journalists was known to have violated severe government press restrictions, unexplained disappearances have become the norm, rather than the exception, during the past several years of political tension here.

Serrat, however, is the first journalist working with a foreign agency to be reported missing.

There are six full-time reporters in the AP bureau here, including four Argentines, a Mexican and Nicholoson, who is a U.S. citizen. Under Argentine law, all of the bureau articles are for foreign publication and may not appeared in local papers.

Although Serrat, had written several articles concerning a series of strikes over the past several weeks and the still-tense labour situation here, AP co-workers said the entire bureau had been involved in the labor coverage and that none of his recent articles could be construed as controversial.

A trained lawyer, Serrat practiced law here for several years before turning to journalism.