Police arrested one youth Friday and were searching for another a day after a gunman opened fire on a crowd outside a high school and wounded four students.

The suspect, who was not identified, was charged with four counts of assault with intent to kill in the incident, which occurred a few hours after two young "outsiders" had argued with students in the cafeteria at Woodrow Wilson High School, police said.According to witnesses, a gunman stepped out of a four-wheel drive vehicle as students were leaving for the day, fired a few shots, then began to shoot randomly.

Three of the victims were shot in the leg and the other was shot in the upper lip, but none of the injuries was serious, hospital officials said.

The shooting, which occurred in an affluent section of northwest Washington, took place one day after a triple slaying brought the city's homicide total this month to 39.

"I am outraged that less than 24 hours after three people were executed on our street, we have four young people wounded," Mayor Marion Barry said. "I am urging the Metropolitan Police Department to spare no resources to solve this case."

The assailants were not students at the school, according to Capt. Robert Gales of the District of Columbia police.

School system spokesman Charles Seigel said two "outsiders" entered the school at about noon and were involved in a "verbal altercation" with students.

The students agreed to a fight after school, Sei-gel said, and were on their way to the site when the shootings occurred.

When asked if any of the victims knew the assailants, Gales said, "I think some of the victims know who was involved."

Andrew Jenkins, superintendent of schools, said he planned to dispatch a crisis intervention team to the school Friday to help students deal with the aftershock of the incident.

School officials also said they would beef up security at Wilson High.

The shootings occurred at about 2:30 p.m. Police said Tyrone Whitfield, 18, was shot in both legs; Kofi Martinez, 17, suffered a superficial wound in the right leg; Jamal Smith, 17, was shot in the right leg; and Lazaro Santa Cruz, 16, was shot in the lip.

Stacy Karageorgos, a sophomore, said she was looking out a window of the school when she saw a man with a gun climb out of a dark-colored jeep.

"He stood out of the jeep and aimed at first. He knew where he wanted to shoot, and then he just started shooting at random," she said.

"At first they were aiming for one person and then they starting shooting randomly," she said.

The shootings came a week after a shooting incident outside a school in Stockton, Calif., in which five children were killed.