Buses from either side of divided Kashmir (search) headed to the heavily militarized frontier between India and Pakistan on Thursday in a new service that will allow Kashmiris to visit relatives separated by decades of enmity between the two rivals.

On the Indian side, passengers hugged Prime Minister Manmohan Singh (search) as they boarded buses decorated with marigold garlands, while Singh described the buses as "a caravan of peace" before waving a blue flag to mark the start of their journey toward the frontier.

At an the conflict between India and Pakistan (search) over the Himalayan region. The two countries decided in February to restart the service as one of the clearest positive steps in their often-stumbling peace process.

The bus service got under way despite an attack by suspected militants on Wednesday on a government compound in Srinagar where passengers selected for the initial trips were staying. Six people were injured but the passengers escaped unharmed.

Most of the region's militant groups oppose any steps forward in the peace process and see the bus service as a gimmick that gets them no closer to their separatist goals. They have vowed to disrupt the service.

The passengers will be seeing relatives who have been separated since 1947, soon after India and Pakistan won independence from Britain.

"The caravan of peace is now on its way, No one can stop it," Singh said at a public rally in Srinagar, the capital of India's Jammu-Kashmir state.

Singh praised Pakistan President Pervez Musharraf for helping Kashmiris realize their dream of uniting divided families.

"The new climate will help India and Pakistan to settle their disputes peacefully," he said.

Sonia Gandhi, head of India's ruling Congress party, also greeted the Kashmiris in Srinagar before they boarded. "The peace process can't be derailed," she said.

In Pakistan-controlled Kashmir, the top elected official, Sikandar Hayyat Khan, asked India to ensure security for the travelers.

"Our brave people are going to Srinagar despite the attack there, and I ask Indian government to provide protection to our people," he said in his speech at a ceremony in Muzaffarabad, capital of Pakistan-controlled Kahsmir.

Early Wednesday afternoon, two militants on the Indian side made it through the gate of a heavily guarded tourism complex where selected passengers were staying, opening fire in the courtyard.

It was not clear how they made it past the guards, but a gunbattle quickly broke out and the main building in the complex caught fire. The passengers, who were in protective custody because of fears they could be targeted by separatists, were in a different building that did not catch fire.

A total of about 50 passengers were riding the buses, half from Pakistani-controlled Kashmir and half from the Indian portion. Most are from families that have been divided. Passengers were to travel to the bridge that spans the frontier, where they were to cross on foot to board buses on the other side and drive to Muzaffarabad or Srinagar.

More than a dozen Pakistan-based rebel groups have been fighting for Kashmir's independence from India or its merger with Pakistan since 1989. At least 66,000 people, mostly civilians, have been killed in the conflict.

Kashmir, the only majority Muslim state in largely Hindu India, is claimed in its entirety by both India and Pakistan, and has been at the root of two of their three wars.