Prince George's County police are investigating the shootings of three men early yesterday that could be connected to fights at local nightclubs, capping a week in which two other men were killed in nightclub quarrels.

At the Supper Club in Oxon Hill, two people were shot about 3 a.m., moments after several patrons involved in a fight had been asked to leave. The two victims were running back into the building when bullets pierced the glass front doors and hit them in the legs.

Police are also looking into whether a man found shot in the head inside a car in the FedEx Field parking lot had been involved in a fracas at yet another club early yesterday. The man remained in critical condition at a hospital yesterday.

"Obviously, we're concerned at the level of violence that has been taking place recently at these nightclubs," said Cpl. Diane Richardson, county police spokeswoman, noting that the spate of episodes was unusual. "I'm certain that in light of these incidents, we'll look and see if there's something we can do."

Last Sunday, David Moncrieffe, 24, of Northwest Washington was shot to death after bumping into another patron at Crossroads Entertainment Complex in Bladensburg, authorities said. And early Thursday, Daniel E. McDowell, 29, of Southeast Washington was fatally stabbed and two other men were seriously wounded after a fight broke out at the Legend Nightclub in Temple Hills.

The episode at the Supper Club began shortly before 3 a.m. yesterday, when several people involved in a fight were told to leave, police said. Soon after, shots rang out in the parking lot on Southern Avenue and the two men were hit. The victims, ages 30 and 29, suffered gunshot wounds to the leg and were taken to a nearby hospital. It is unclear whether either was involved in the original fight. Police declined to identify the hospital or the victims because they are potential witnesses.

Also at about 3 a.m., Prince George's police found the man with a gunshot wound in the Landover parking lot. Witnesses told police that the 20-year-old had just left the Mad Chef Cafe in Capitol Heights in a car with three friends. They told police they noticed that they were being followed and that a car with at least two people pulled up and someone opened fire. Police are investigating whether the shooting is connected to an earlier altercation.