A Lancaster man under investigation in the sale of high-powered weapons to Mexican drug traffickers is expected to plead guilty to a federal firearms charge next week, court records show.

Members of a U.S. Alcohol, Tobacco, Firearms and Explosives task force arrested Erasmo Arciba in September as part of an ongoing investigation into weapons sales to the Zetas, a group of mercenaries employed by Mexico's Gulf Cartel.

Authorities believe Mr. Arciba used 21-year-old Angilita Ortiz of Grand Prairie and other "straw purchasers" to buy handguns and assault rifles in the Dallas area.

Federal court records show that Mr. Arciba filed paperwork Thursday in which he admitted being a convicted felon in possession of firearms.

Mr. Arciba did not enter into a plea agreement, but his court-appointed attorney Carlton McLarty said the Lancaster man is expected to plead guilty to the charge during a hearing next week.

Testimony during other hearings in the case indicated that the 42-year-old contractor is believed to have traveled to the border to deliver the weapons, but Mr. McLarty said his client denies direct ties to the Zetas.

"He has no idea as to the ultimate destination of the guns," Mr. McLarty said. "He was asked to buy these guns by another person."

Mr. McLarty declined to say whether Mr. Arciba has cooperated with investigators.

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