PANAMA CITY – The opposition Democratic Revolutionary Party (PRD) said Tuesday that Dec. 20 should be a “day of national mourning” to mark the U.S. invasion of Panama, which began on Dec. 20, 1989.

“The death of an undetermined number of Panamanians, the destruction of property representing thousands of millions of balboas (1 balboa = $1) to the national economy, the psychological and spiritual damage done, cannot be ignored by authorities and society,” the PRD said in a statement.

Anywhere between 500 and 5,000 Panamanians, according to the official account, were killed in the U.S. military expedition to apprehend the Central American country’s then-ruler, Gen. Manuel Noriega, who faced federal drug charges in the United States.

Noriega surrendered 13 days into the U.S. military operation.

The PRD urged all of its supporters to take part in Tuesday’s events marking the 27th anniversary of the invasion.

“Remember our martyrs and do not forget the infamy that our aggressors wrongly called ‘Just Cause,’” the party said.

Panama established in July a commission tasked with clarifying the events of December 1989 and producing an authoritative list of the dead.

“We believe that the names of all the victims identified by the commission should be inscribed forever on a national monument that serves as testimony to the new generations. What occurred (in 1989) should serve to build a comprehensive vision of our international relations with self-determination and to ensure our neutrality and vocation of peace,” the PRD said.

Washington’s interventionist policy persists to this day, the party said, pointing to the effects on Panamanian companies that find themselves on what is known as the Clinton List, which targets firms allegedly engaged in laundering proceeds from drug trafficking.

Two of Panama’s major newspapers, La Estrella and El Siglo, have been crippled financially because the U.S. Treasury added their owner, Abdul Waked, to the Clinton List in May.

The Panamanian government has asked the U.S. to lift the sanctions affecting the dailies so they can continue to operate for another year.