COLOMBO, SRI LANKA, NOV. 9 -- A bomb exploded in a vehicle on a busy road in the Sri Lankan capital today, killing 32 persons and wounding 106, police and hospital sources said.

They said several of the wounded were in serious condition and the death toll could rise to 50.

Bodies and body parts littered the area, and the air smelled of burning flesh. The bodies of six women lay crumpled at a street corner. Two charred corpses were stretched out in a van.

The bomb exploded during the afternoon rush hour while thousands of people waited for buses to the eastern suburbs. It went off 50 yards from a police station in Colombo's working-class Maradana district, two miles from the room where President Junius Jayewardene was discussing two controversial bills aimed at ending a four-year-old rebellion by militants among the island nation's Tamil minority.

State-run television said intelligence sources suspected that an outlawed Marxist group, the People's Liberation Front, was responsible for the blast.

There was no immediate claim of responsibility.

The front, which includes nationalist members of the majority Sinhalese community, opposes the terms of Jayewardene's July 29 pact with India to end Sri Lanka's conflict with Tamil rebels.

The bills spell out the powers of semiautonomous provincial councils to be set up under the peace pact. The councils are designed to meet Tamil demands for a homeland.

Jayewardene and Indian Prime Minister Rajiv Gandhi have both escaped serious injury in attacks, blamed on the front by the government, since they signed the accord.

The accord, and the Indian troops who were invited here by the Jayewardene government to help enforce it, have fanned Sinhalese nationalism. The accord and the Indian troop presence also appear to have emboldened the militants, who believe the peace pact gives too many concessions to the Tamils.

According to official government figures, the People's Liberation Front, a militant Sinhalese leftist group, has killed at least 38 people since the accord was signed. In recent days, the front has threatened to attack government officials in Colombo as part of its campaign against the accord.

Most Tamils are Hindus, the predominant religion in India. They make up 18 percent of Sri Lanka's 17 million people and say they are discriminated against by the mostly Buddhist Sinhalese, who control the government and military.

A police spokesman said the bomb, estimated at 110 pounds of high explosives, went off despite heavy security after front threats to disrupt government activities.

Police said several government members of Parliament had received anonymous threats warning them not to support the bills, which are to be debated in Parliament Tuesday.

Police said the bomb appeared to have been planted in a bus moving toward Pettah, the heart of the city where a car bomb apparently set off by Tamil guerrillas killed more than 100 people in April.

D.S. Wijeratne, a 51-year-old teacher, said the bomb went off 150 yards ahead of her as she walked towards her brother's shop.

"The smoke and flame rose to about twice the height of the coconut trees," she said.