An Israeli Embassy spokesman, Israel Mey-Ami, said in a telephone interview: ''He was not here in any official business, and he did not contact the embassy. I don't know how long he was in this country, but it musn't have been very long.''

Mr. Mey-Ami said that he went to Morelia, the Michoacan state capital, on Thursday to pick up Mr. Mir's body and bring it to Mexico City. He said it would be returned to Israel.

A spokesman for the state Attorney General's office, also acknowledging that Mr. Nir was traveling under the name of Pat Weber, said he did not know why he was using as assumed name, and Mr. Mey-Ami said he had no further details.

Mr. Nir arrived in Mexico City on Sunday and traveled to Uruapan, 190 miles west, to stay with friends. ''It appears he had some possible business involving shipments of products from Latin America to Europe,'' the spokesman said.

Dov Schmorak, the Israeli Ambassador, said on Israeli army radio that Mr. Nir apparently missed a regularly scheduled flight to Mexico City and hired a private plane.