Reacting to reports of election fraud and voter intimidation, the Liberian government today acknowledged some "errors" in the conduct of yesterday's presidential balloting.

"I am going to concede that one or two errors were made and these errors are being looked into by the Special Elections Commission right now," said Carlton Karpeh, the minister of information.

His statement followed complaints from opposition political parties that the military government improperly allowed voting to take place in military barracks.

In one Army barracks here in the capital, voters were free to vote as many times as they wanted, witnesses said. Opposition party observers were not allowed to watch voting in the barracks, as is required under the election law.

Yesterday's election pitted Liberia's military leader, Samuel K. Doe, against three civilian opponents. Five years ago, after a coup in which the president and 13 government officials were shot, then-master sergeant Doe seized control of this West African nation.

The results of the election, in which voters here also selected members of a House and Senate to serve in an American-style government, do not have to be announced for two weeks.

The U.S. government, which is by far Liberia's largest foreign aid donor, is monitoring the voting. Congress has demanded that U.S. assistance, $86 million this year, be withheld if the election is not found "free and fair."

Voter turnout was reported heavy. In Monrovia, there were half-mile lines outside polling centers, and thousands stood in the 90-degree heat for up to 10 hours.

Both government officials and opposition party leaders said today that in many of the country's 1,800 polling locations voting was completed without violence or major violations of election rules.

Two opposition parties, however, demanded that none of the ballots cast at Army barracks be counted. The Liberian Action Party and the Unity Party said the soldiers should vote again in properly supervised polling centers.

Preliminary and unofficial election reports today indicated strong support for Liberian Action Party candidate Jackson F. Doe, who is not related to the head of state. He appeared to be running ahead of Samuel Doe.

Byron Tarr, secretary general of the Liberian Action Party, said his primary worry "is what happens to the ballot boxes."