A Manila slum leader was ordered freed yesterday apparently as a result of U.S. interest in her arrest and reports that she had been tortured.

Philippines President Ferdinand E. Marcos ordered Trinidad Herrera, 35, released two days after the first story of her imprisonment appeared in the U.S press and a day after the State Department announced it had expressed deep concern to the Philippines government.

It was understood the U.S charge d'affairs in Manila made U.S. concern known in a meeting with Marcos.

Herrera was arrested April 25, but the Philippines government announced neither her arrest nor the reason for it.

In ordering her release, Marcos said a police lieutenant and others who interrogated her would be court-martialed.

Her lawyer, former Sen. Soc Rodrigo, who first to charge that she had been tortured. A letter to Marcos by 15 Catholic bishops supported the charge.

At the invitation of the Philippine's government, two U.S. Embassy officials visited Herrera in prison Thursday. They did not comment on whether she had been tortured.

Herrera is president of an organization in Manila's large Tondo slum district and had frequently been invited to confer with Marcos and his wife Ymelda Marcos, who is Manila's governor, about slum conditions.

The State Department expressed pleasure that she had been released and that an investigation into the circumtance was continuing.

The World Bank postponed approval of a $15 million resettlement loan tot the Phillipines Thursday at the suggestion of Canadian Director Earl Drake.

Drake said he wanted to ascertain whether Herrera's arrest had any connection with her past comments on a World Bank project in Tondo. She had raidesquestion about he still aspects of the project. Drake said he still does not know whether her detention was related in any way to the bank's project.

The loan is scheduled to be considered at Tuesday's directors' meeting.