A U.S. Senate committee Tuesday focused its attention on the situation in Sri Lanka, where the military is engaged in an intense battle with Tamil Tigers as the two sides struggle for control of what is believed to be the last of the rebel strongholds. Witnesses at the Senate hearing decried the actions of both sides in one of Asia's longest running wars.

Anna Neistat, senior researcher for Human Rights Watch, told a Senate Foreign Relations committee hearing that human rights violations are being committed by both sides in Sri Lanka's 25-year-old conflict.

She described a deplorable situation in the so-called safe zone, established by the government to protect refugees. "We received several detailed accounts from people who stayed within the safe zone, and these accounts suggest that the shelling by Sri Lankan forces killed dozens if not hundreds of people inside there," she said.

But Neistat is equally critical of the rebel Liberation Tigers of Tamil Eelam, or LTTE. "The LTTE has deliberately prevented civilians under its control from fleeing into the government controlled areas. We have documented several incidents where LTTE forces fired at fleeing civilians, killing and injuring dozens. We also documented cases where the LTTE effectively used civilians as human shields to protect their positions from attack. This is a war crime," she said.

Other witnesses described what they called the Sri Lankan government's growing assault on dissent.

"Many Tamils have been abducted and have simply disappeared. It is sad to say that it is almost a certainty that these attacks have been carried out by elements of the government. Impunity seems total. Nobody has been prosecuted for any of these incidents," said Jeffrey Lunstead, a former U.S. ambassador to Sri Lanka.

Lunstead also noted that journalists have come under attack, a point echoed by Bob Dietz, Asia Program coordinator at the Committee to Protect Journalists. "Top journalists have been killed, attacked, threatened and harassed since the government began to pursue its all-out military victory against the LTTE. Many local and foreign journalists and members of the diplomatic community firmly believe the government is complicit in these attacks," he said.

Ambassador Lunstead said the world community could play an important role in shaping Sri Lanka's future. He recommends that international donors impose conditions on economic aid to the government of Sri Lanka. He says those conditions should include an improvement in the country's human rights record, the resettlement of displaced persons and a devolution of power from the capital, Colombo, to local areas to allow all Sri Lankans to have a greater say in how they are governed.

Anna Neistat of Human Rights Watch is urging the United Nations Security Council to hold a special session to address Sri Lanka's humanitarian catastrophe.

Senator Bob Casey, a Pennsylvania Democrat, chaired the hearing. He called for both sides in the conflict to come to a political settlement. "Should the war end and the broader Tamil population continue to face systemic discrimination by and inadequate representation in the Sri Lankan government, the Tamil Tigers may once again be driven underground to carry out acts of terror, perpetuating another go-around in this vicious cycle of violence. So far, there are few indications that a political deal is imminent. The government of Sri Lanka will not negotiate directly with the LTTE, but it does not appear the government has much interest in finding alternative Tamil interlocutors, nor have the Tamils presented credible alternatives to the LTTE," he said.

Sri Lanka's military says its forces advanced Tuesday into the last rebel stronghold in northeastern part of the country.

The LTTE has said it is open to a limited cease-fire and a political solution, but has rejected calls to disarm. The government has rejected anything short of the rebels' unconditional surrender.