Mexico (search) is investigating what a Pakistani national wanted by the United States for allegedly selling anti-aircraft missiles was doing in a beach community outside Tijuana, President Vicente Fox's spokesman said Thursday.

Acting on intelligence provided by the United States, Mexican authorities captured Arif Durrani (search) earlier this week as he left a restaurant in Playas de Rosarito, near the Tijuana-San Diego border, spokesman Ruben Aguilar said.

Durrani, 55, had entered Mexico from the United States (search) but at the time of his arrest could not provide documents proving he had done so legally, Aguilar said.

Durrani was deported by Mexico late Wednesday, but he was taken into U.S. custody when his flight to Pakistan stopped in Los Angeles.

Aguilar said Mexico has not charged Durrani with wrongdoing, but its authorities were still investigating.

"Arif Durrani is facing an arrest warrant in the United States for the crime of international trafficking of anti-aircraft missiles," Aguilar said. "He is a fugitive from U.S. justice."

Aguilar noted that Mexico does not produce such missiles.

Durrani, a former U.S. resident, was convicted in the United States in 1987 of selling missile parts to Iran and served five years in prison. He was deported from the United States in 1998 and apparently has lived in Mexico since then.

It was unclear whether the current investigation was related to Durrani's prior conviction. He had claimed to have acted as part of the 1980s Iran-Contra scandal, in which arms were sold to Iran to finance Nicaraguan rebels when the U.S. Congress had barred such aid.

In 2003, Durrani petitioned a U.S. court to have his conviction overturned and asked to review more government documents to try to prove he sold the parts at the behest of former Lt. Col. Oliver North and other U.S. officials.

Durrani claims he was part of Washington's effort to exchange arms for American hostages held in Lebanon. He said North, a former National Security Council aide, told him to ship the missile parts to Iran and not to worry about getting an export license.

Durrani was detained with three Afghan-born men and a Syrian, all of whom apparently entered Tijuana from the United States. Aguilar said Thursday the other four were simply detained on immigration violations "and nothing else."

The Afghans and the Syrian are U.S. citizens or residents, and all were deported to the United States on Wednesday.