A Panamanian government official suggested the United States might have staged a chase of its ambassador's car to justify an eventual military evasion.

The U.S. Embassy said Ambassador Arthur Davis was pursued for two miles in Panama City on Sunday by a government military vehicle with its siren blaring. It called the incident serious.Sunday's communique signed by Justice Minister Rodolfo Chiari de Leon said the incident began when a police sergeant saw civilians in three vehicles following the ambassador's car with "an exaggerated display of automatic arms."

"We do not want to think that they are fabricating false accusations against our armed forces to justify an announced invasion of Panama, and we reiterate the intent of the Panamanian government to protect the life and property of residents and foreigners, including North Americans," the communique said.

There was no immediate U.S. Embassy reaction to the statement.

The United States is sending 1,300 additional troops Tuesday. Troops were loading weapons and supplies into helicopters Monday in the United States in preparation.

American officials have said the forces are intended to protect U.S. bases and American citizens. Washington has declared it will not use military force to oust Gen. Manuel Antonio Noriega, whose leadership has been the focus of a national political and economic crisis.

Sunday's edition of the government-run newspaper La Republica quoted pro-government labor leaders as urging Panamanians to prepare for an American invasion when the additional troops begin arriving.

There are 10,000 troops stationed at the U.S. Southern Command in Panama. Pentagon officials said more troops may be sent if needed.

Embassy spokesman Terence Kneebone said Davis was leaving the home of Vatican Ambassador Jose Sebastian Laboa when the Panamanian vehicle "began following immediately, picking them up right outside the gate." He said it tried to stop the chauffer-driven car with its lights and sirens.

"The ambassador's driver, in accordance with instructions, did not stop. The ambassador was driven to his residence, and the other vehicle followed all the way," Kneebone said. The residences are about two miles apart.