MEDAN, Indonesia -- The black-and-white banner hanging above a knot of student protesters at the University of North Sumatra had a blunt message for Indonesia's President: "Fire Suharto and try him."

But after three days of riots, looting and near-anarchy in this Sumatran city, the words seemed almost like a return to law and order. About 200 students marched around the campus peacefully Friday, chanting "Suharto is the son of Satan!" and demanding political reform. It was in stark contrast to earlier in the week, when the protests spilled into the streets and mutated into an ugly urban rampage.

As Indonesia comes to the end of its worst week of social unrest in years, the leaders of the student movement here are struggling to understand the forces they have unleashed. In Medan, angry mobs looted stores, smashed windows and set cars ablaze. A movement for political reform turned abruptly into an economic explosion aimed at the city's ethnic Chinese minority.

"We do not want anarchy or a coup d'etat," said Rosmery, a lecturer in political economy who coordinates the student protests at the University of North Sumatra. "The student movement wants to take the peaceful way. What happened here this week was not the student movement."

Yet Ms. Rosmery, who like many Indonesians has only one name, acknowledged that some students had taken part in the violence. The three days of clashes with military and security forces resulted in at least one death and scores of injuries, while the looting left 170 stores gutted. Ms. Rosmery refused to blame any group for resorting to violence, saying only that she had asked the students to stay on campus until tensions eased.

Indonesia's defense minister, General Wiranto, also demanded that students stay behind campus gates. After touring Medan on Wednesday, Gen. Wiranto, who is also head of the armed forces, said the riots were caused by "criminals" and said the army would take strong measures to root them out.

Some students contend that the violence was fomented by a "third party" seeking to discredit the movement by deflecting attention from Indonesia's real political problems and Suharto's government.

Still, with Indonesia's economy in a spiral, political experts here say the student movement could easily turn violent again. The main spur for this week's mayhem was the government's announcement on Monday that it would raise the price of gasoline by 70 percent. Within two hours people began ransacking shops and overturning cars.

"This is economic rather than political," said Joseph Budi Harsono, an ethnic Chinese merchant who owns an automotive-parts store here. "It's the result of a social gap. Too many people are being laid off."

Harsono, who is 48, rubbed his eyes wearily. He had been awake for almost three days, guarding his store from gangs that have torched dozens of Chinese-owned businesses. Harsono showed off a bottle of battery acid that he kept handy to throw at anyone who threatened him.

The ethnic Chinese account for 2 percent of Indonesia's population but own a majority of the nation's private wealth.

With the economic crisis, it has resurfaced in a virulent form. Stores all over Medan carry signs that say they are owned by "pribumis," indigenous Indonesians. On some streets, burned-out Chinese shops stand next door to pribumi shops that have not been touched.

"The Chinese are snobby about their wealth," said Kamal Daulay, a 36-year-old rickshaw driver. "They control the economy. We don't like them."

The Chinese are responding with a mixture of defiance and retreat. While the shopkeepers are creating neighborhood defense teams that warn each other of trouble over walkie-talkies, more affluent business people have moved their families into hotels, or are jumping on flights to Singapore and Jakarta.

"The government is right to open fire," said Husin Effendy, a Chinese shopkeeper. "They burn down our shops and steal our things."

At times it is hard to figure who is more reviled here -- Suharto or the ethnic Chinese. Last Saturday dozens of youths smashed the windows of a car dealership that sells Timor automobiles, the national car of Indonesia, then dragged out a car and set it alight on the street.

People in the neighborhood say the gang was motivated by hostility toward Suharto. The Timor company is controlled by his youngest son, Hutomo Mandala Putra, widely known as Tommy. But a young man sitting inside the empty showroom said he believed the gang had been aiming at the owner of the dealership, an ethnic Chinese.

"This is a political issue," he said. "We just happen to be the victims."