A Georgetown restaurateur was arrested yesterday on a grand larceny charge as he stepped outside an Arlington courtroom where he had declared himself innocent of a wealthy Northern Virginia woman's allegations that he cheated her out of at least $180,000.

Angelo Carrasco, owner of the Las Pampas restaurant, was charged by police with the theft of a 1.55-carat diamond from the 60-year-old widow whose lawsuit against him led to the criminal charges.

The woman, Carole M. O'Connor, testified yesterday in Arlington Circuit Court that Carrasco, who has White House press credentials as an Argentine television journalist, bilked her out of the money in a fraudulent scheme to establish a documentary film company.

"I feel this man has taken all my money and used it for purposes other than I intended and I want it back," she told Judge Charles H. Duff.

Carrasco had completed denying her allegations during a three-hour hearing on her lawsuit when he was arrested by detectives on a charge of stealing the diamond the officers said was valued at $11,000.

Carrasco had asserted that O'Connor had encouraged the television project and willingly funded it and said that he had been busy preparing television documentaries on South and Central America.

He was being held last night under $100,000 bond.

Both Carrasco and his attorney, Ronald M. Cohen, argued that Carrasco was involved in "an ongoing, legitimate function. It was a substantial venture he was involved in and not just a sham operation."

Among items found in a recent police search of Carrasco's apartment at The Representative condominium at 1101 S. Arlington Ridge Rd. was a diamond that O'Connor has claimed belonged to her.

She alleges in court documents that Carrasco switched the real diamond for a "simulated diamond" when he supposedly designed a gold ring made from the fillings in her late husband's teeth -- a "bizarre request" from her late husband that O'Connor said in an affidavit she honored.

She also alleges that Carrasco showed up at her Arlington home with an acetylene torch to melt the gold.

In his testimony Carrasco denied any knowledge of her ring or diamond.

He said the diamond found in his apartment was one he was keeping as collateral on a loan he cosigned so a friend, Luis Toledo, could buy a van.

Toledo testified the diamond was an heirloom from his family.

Duff continued the hearing on O'Connor's petition to attach Carrasco's assets until April 13 and set a July 6 trial date for the suit.