YANGON (AP) -- Myanmar announced Tuesday it was releasing 6,300 prisoners in a widely expected amnesty by the newly elected government, but it was not clear how many of them were political detainees.

The release of some of the country’s estimated 2,000 political prisoners has been hotly anticipated as part of liberalizing measures since Myanmar’s long-ruling military government handed power in March to a military-backed, civilian administration.

State radio and television said 6,359 inmates would be released beginning Wednesday under a humanitarian amnesty by President Thein Sein for inmates who are old, disabled, unwell or who had shown good “moral behavior.”

However, the reports did not specify how many were political detainees. Myanmar’s government has long maintained that political prisoners are not a separate class and that all inmates in the country have been convicted under criminal law.

Relatives and supporters of political detainees were excited by the announcement, but wary, given that they could not be sure who would be among those released.

“We welcome the amnesty announcement. This is very good news and we hope that political prisoners will be among those freed,” said Nyan Win, a spokesman for democracy movement leader Aung San Suu Kyi.

The president instituted an earlier amnesty soon after taking office, but it included just a few dozen political detainees.

Most prominent political prisoners, including many affiliated with ethnic minorities, are held in facilities far from the country’s main city of Yangon, in a policy apparently aimed at limiting their ability to communicate through visiting family members and lawyers.

Myanmar’s tightly controlled state newspapers had published an appeal Tuesday morning for a release of political prisoners who no longer represent a threat to stability, in a sign that such an amnesty had official blessing.

The appeal in the three state newspapers, which closely reflect government positions, was an open letter from the government-appointed National Human Rights Commission calling on Thein Sein to grant an amnesty as a gesture of magnanimity.

The new government is seen as remaining closely aligned with the military, but has declared its intention to liberalize the country’s hardline policies.

The United States believes Myanmar’s elections were flawed but has been encouraged by its liberalizing trend since the civilian administration took power, the highest-ranking American diplomat for Asia said Monday.

U.S. Assistant Secretary of State Kurt M. Campbell, speaking at a lecture in the Thai capital, Bangkok, cited “dramatic developments under way” in Myanmar and said Washington may soon take steps to improve its relationship with the country.

“I think it would be fair to say that we will match their steps with comparable steps and we are looking forward in the course of the next several weeks to continuing a dialogue that has really stepped up in recent months,” he said.

Campbell cited a “very consequential dialogue” between Thein Sein and democracy leader Aung San Suu Kyi as a major positive development. In public speeches, Thein Sein also has appeared conciliatory about easing limits on freedom of speech and holding talks with ethnic rebels.

The United States has long ostracized Myanmar with political and economic sanctions because the failure of the former military government to hand over power to a democratically elected government and poor human rights record.

The U.S. could ease restrictions on financial transactions and travel by top Myanmar officials, and also unblock aid by some multilateral agencies as well as resume its own assistance.