FUGITIVE SOUGHT IN SLAYING OF U.S. DRUG AGENT HID IN MEXICO

WASHINGTON, July 16 -- For nearly six years, Agustin Vasquez Mendoza
was the perfect fugitive.

Sought by federal authorities in the United States and Mexico in one
of their biggest joint manhunts ever, the man suspected of ordering
the 1994 killing of an American narcotics agent vanished into the 19th
century.

He shunned cell phones and other modern communications, said American
law enforcement officials. He severed ties to relatives and began a
new family under a stolen name. He lived simply in some of Mexico's
most remote corners, shielded from the police by ruthless neighbors,
dense vegetation and terrain best managed on burro or horse.

"He was living the life of a Mexican bandit from the last century,"
said Michael G. Garland, the Drug Enforcement Administration official
who led American efforts in Mexico to find the killer of a Phoenix
undercover agent, Richard Fass.

The longer Mr. Vasquez eluded authorities, the more his legend grew.
He made the F.B.I.'s ten most wanted list. When a $250,000 reward
offered by the F.B.I. and the drug agency failed to get results, the
State Department sweetened the pot, for a total of $2.2 million.

On July 9, the Mexican police finally seized Mr. Vasquez and flew him
to Mexico City under the control of two generals and
machine-gun-toting guards.

"When I saw him, he was terrified," Mr. Garland said in a telephone
interview from Mexico. "His hands and feet were shaking." The prize of
a manhunt that had cost millions of dollars and tested the often
bitter relations between Mexican and American law enforcement agents
was all of 5 feet 3 inches and 110 pounds. "He looks like a teenager,"
Mr. Garland said.

Mr. Vasquez, 30, is being held on charges of ordering the June 30,
1994, killing of Mr. Fass, who, working under cover, tried to buy 22
pounds of methamphetamine from three associates of Mr. Vasquez in
Glendale, Ariz. The associates, all of whom have been sentenced to
prison, shot Mr. Fass seven times, including twice in the face.

Mr. Fass, 37, was killed on his last undercover mission before being
transferred to a desk job. In his dangerous work, he had repeatedly
changed his appearance and plucked hair from his nostrils to give
himself an addict's sniffle, said his brother, Guillermo.

His death was "shattering for all of us," Guillermo Fass
said.

For his colleagues, avenging that killing was personal, said Tom
Raffanello, the Phoenix special agent in charge. His agents asked to
be rotated into Mexico City -- two or three at a time -- to join a
team of 45 narcotics agents whose top priority was to help the Mexican
police find Mr. Vasquez, officials said.

For the next several years, Mr. Vasquez was believed to be continually
on the run, moving among rural hideouts, inaccessible by car, in
mountainous Michoacan, his home state, the steamy Campeche region and
Puebla, southeast of the capital.

In such areas, the Mexican police were often thwarted by the locals'
deep distrust of federal authorities. Mr. Vasquez encouraged the
complicity of his neighbors by taking on the last name of Cornejo, a
feared drug-trafficking family, Mr. Raffanello said.

"I'd compare it to the John Gotti people in certain areas of Queens or
Brooklyn," said Mr. Raffanello, who was one of the original
investigators in the slaying of another Drug Enforcement agent,
Enrique Camarena, in Mexico in 1985.

Mexican authorities arrested a dozen Vasquez look-alikes over the
years. An important break came when Mr. Vasquez married in Campeche.
The thumbprint on his marriage certificate matched a print held by the
United States immigration service, which had previously arrested him,
officials said.

They said Mr. Vasquez, who fancies himself a ladies' man according to
his F.B.I. wanted poster, was done in by a simple errand for his wife.

Through telephone intercepts, authorities discovered that his
electronic silence had slipped. On Sundays, he was placing regular
phone calls to the relatives of his wife, with whom he has a
2-year-old son and an 11-month-old daughter.

Still, the pay phone was not easily traced because it had a fixed
cellular connection. American agents were enlisted in the painstaking
process of homing in on it through ground surveillance and high
technology -- a "burros and satellite" operation, as one official
called it. Other clues were provided by the street noise in the
background as Mr. Vasquez chatted, officials said.

He was arrested while talking on the phone in Tehuacan,
Puebla.

American officials praised the Mexican federal judicial police for the
arrest. The cooperation marked a bright point in a frequently troubled
relationship. Events from the Camarena killing to the 1997 arrest of
Mexico's top antidrug official have fueled suspicions in both countries.

American agents acknowledge withholding information on the ground that
their Mexican counterparts are corrupt, and Mexican authorities have
sought to curb what they see as vigilantism and meddling by American
agents beyond American borders.

Cooperation between the two nations has improved since Mexico
undertook a comprehensive overhaul of its justice system, said Jose
Antonio Zabalgoitia, a spokesman for the Mexican Embassy here.

"The relationship in the law enforcement area has become more mature,"
he said. "We both are aware of what is important and sensitive to the
other side."

Still, one highly sensitive matter remains. The United States has
requested the extradition of Mr. Vasquez. It is gathering evidence to
submit to Mexico within 60 days.

But Mexico's courts are divided over the constitutionality of
extradition, and the Supreme Court is currently reviewing the issue.
Mexican law, moreover, bars extradition in cases of capital punishment.

"We have to give assurances that we will not seek the death penalty,
which we are prepared to do," said John Russell, a Justice Department
spokesman. Asked about the prospects for extradition, he added, "We
are hopeful."