U.S. Army officials are investigating allegations that two female soldiers refused to drive a truckload of troops into what they believed to be a dangerous area in the first hours of the U.S. invasion of Panama, according to Defense Department officials.

The two enlisted women, who were assigned to drive trucks for an Army support battalion, allegedly refused orders to drive the troops into a section of Panama City that was riddled with sniper fire nine hours after the invasion began Dec. 20, officials said yesterday.

"They felt it would endanger the lives of the combat soldiers that they were going to transport if they took them into that area," said one official familiar with the investigation.

A commander ordered the women out of the truck and replaced them with two other drivers, who then drove the troops into Panama City, one official said. The official said it is unclear whether the substitute drivers were male or female. Officials said there are no other known reports of similar incidents.

Pentagon officials said an unconfirmed report of the incident indicated that one of the women was crying during the confrontation with her commander.

U.S. Army officials in Panama are investigating the incident to determine whether the soldiers should be reprimanded or charged with refusing to obey orders, sources said.

The alleged incident is likely to fuel the controversy over the role of women in combat, which was rekindled by the Panama invasion. During the operation, Capt. Linda L. Bray became the first woman to order U.S. troops into combat when her military police unit encountered hostile fire at a Panamanian military dog kennel early in the invasion.

Under U.S. military policy and federal law, women technically are not allowed to serve in combat jobs. The invasion of Panama demonstrated, however, that women serving in support roles are likely to encounter combat situations.

The two women enlisted soldiers under investigation were part of the 193rd Support Battalion, which provides logistical services, such as tranportation, refueling and ammunition resupply to combat infantry.

The unit was permanently assigned to Panama and included 571 men and 73 women. Of those women, four were truck drivers, officials said.

About 600 women were among the 26,000 troops used in the Panama invasion. Women make up about 11 percent of the armed forces. Increasing numbers of women are serving in support units that provide logistics services to combat units.