The military government said today that certain officials of state-owned corporations, apparently including some Americans, would be detained or kept under house arrest pending scrutiny of company accounts.

At the same time, the government imposed martial law throughout the country and suspended the country's constitution indefinitely.

In another development, American diplomatic sources revealed that the foreign minister of the ousted regime, who was executed three days ago by firing squad, was given temporary refuge in a U.S. diplomat's home but had not been eligible for permanent asylum under current U.S. policy guidelines. The incident has provoked a congressional inquiry into U.S. policy on asylum worldwide.

Despite the announced detention of state company officials, Economic Affairs Minister Togba Nah-Tipoteh said Liberia's U.S.-style free market system would continue to function unless "all parties concerned reach mutual agreement" on changes in economic policy.

The house arrests of company officials would be maintained, Justice Minister Chea Cheapoo said, until the government had been able to scrutinize the accounts of the various state-owned corporations. There have been allegations of widespread corruption under the previous regime.

In a related development, Cheapoo said about 100 officals and allies of the Tolbert government were on the new regime's wanted list. The figure reportedly includes 17 people already executed in the wake of the coup.

Cheapoo did not say how many company officials would be detained under house arrest, but Western diplomatic sources said the number of Americans affected was about 20. There are an estimated 5,100 U.S. citizens in the country.

Referring to the expatriate detainees, Cheapoo told a news conference that "they will be able to stay at home with their air conditioning."

[In Washington, U.S. officials said it was their understanding that Liberian managing directors and deputy directors would be fired, but their expatriate counterparts would remain at their jobs. Liberian comptrollers were to be arrested and expatriate comptrollers placed under house arrest. According to these calculations, the officials said their initial estimate was that only one American would be affected.]

The United States is Liberia's biggest trading partner and the value of American investments in Liberian rubber, coffee, cocoa, timber and iron mining interests was believed to exceed $1 billion.

Officials in Washington said 43 American firms were represented in Liberia. Among them were Firestone, B. B. Goodrich, a joint venture of Bethlehem Steel called LAMCO and the American International Underwriters Overseas Ltd. insurance firm.

[U.S. banks with affiliates in Liberia include Chase Manhattan, Citibank and Chemical Bank.]

The economic affairs minister's statement that the economy would still be run "basically by the private sector" was seen by independent observers as an effort to assure American investors that their assets were safe.

The imposition of martial law and suspension of the constitution were regarded as a further effort by the ruling People's Redemption Council to consolidate power in the wake of the April 12 military coup led by Master Sgt. Samuel K. Doe. President William R. Tolbert Jr. was assassinated in the coup and on Tuesday a dozen other top government and political officials were executed by firing squad.

Cheapoo said the council would exercise all executive and legislative powers in Liberia while martial law was in force.

The failure of the United States to give sanctuary to former foreign minister C. Cecil Dennis, meanwhile, has prompted a congressional inquiry into the worldwide U.S. policy of only providing asylum when a person is being "chased by a mob." Dennis was among those executed Tuesday.

Rep. Stephen J. Solarz, (D-N.Y.) had charged Tuesday that the U.S. Embassy in Monrovia had used technicalities to reject an inquiry by Dennis about asylum in the early hours of April 12, following the assassination of Tolbert.

The House Africa subcommittee will hold a hearing next Tuesday to examine the circumstances of Dennis' asylum inquiry and his subsequent execution, as well as U.S. asylum and refuge policy worldwide.

The deputy chief of mission at the U.S. Embassy in Monrovia, Julius Walker, was in charge of the embassy on the morning of the coup. He talked to Dennis by telephone shortly after dawn and said Dennis was not refused asylum. Ambassador Robert Smith was in Washington at the time of the coup.

"We did not refuse asylum to anyone," said Walker. "There were no requests," Walker added, refusing to elaborate.

Knowledgeable sources described the late Dennis' conversation with Walker "as tense and distressed" as both men, who had grown close, knew there was virtually nothing Walker could do to help Dennis.

American diplomats defended the policy of not granting asylum because "to have it otherwise would put American lives in jeopardy." One said "if we had given Dennis asylum, we would have had a trail of government ministers filing into here and when the soldiers found out they would have been coming here to get them."

"It would have been dangerous," the U.S. diplomat said. "The [new military rulers] we're dealing with do not understand diplomatic niceties."

In Washington, however, both Solarz and other informed sources said Dennis had asked specifically about asylum procedures at the time of the coup, was given the "mob in the streets answer" and then made no formal request for asylum. Walker's statement that no request had been made therefore was only technically correct.

Solarz asserted that Dennis was reduced to asking the Soviet ambassador for help in arranging a safe transport out of the country, but was told the Russians could not find a car.

[The New York Democrat said, "the consequences of our inaction are enormous, not only in terms of Mr. Dennis' death, but also as a precedcent for requests for American asylum."]

One U.S. source here said Dennis was aware of the U.S. policy on asylum and said "it was discussed with him last April" when current Foreign Minister Gabriel Baccus Matthews unsuccessfully sought asylum at the U.S. Embassy when he was being hunted by the policy of the Tolbert government.

Dennis took refuge in the American diplomat's home on the day of the coup for about 12 to 14 hours, knowledgeable sources said.

While there, he called at least three embassies -- two of them those of African nations -- to arrange for safe conduct to the executive mansion to give himself up. All three refused.

The sources said Dennis did not ask American diplomats to provide the escort and was finally accompanied at about 4 p.m. or 5 p.m. to the mansion by a cousin, Max Dennis, who was a member of the mansion staff.