It was considered unsafe to release the prisoners.

释放这些囚犯被认为是危险的。

《牛津词典》

The release of prisoners was used as a bargaining chip.

释放战俘被用作讨价还价的筹码。

《牛津词典》

They have demanded the release of three prisoners as a precondition for any negotiation.

他们要求释放3名囚犯作为谈判的先决条件。

《柯林斯英汉双解大词典》

It calls for her immediate and unconditional release, as well as the release of the more than 2,000 political prisoners in Burma.

VOA: standard.2009.11.20

Diplomatic efforts to pressure Burma's military towards reform and to release political prisoners have accelerated with the trial.

VOA: standard.2009.05.31

Noriega says maintaining sanctions will give the U.S.leverage to press Cuba's rulers to release political prisoners and grant their citizens political rights.

VOA: standard.2009.05.06

"If President Obama wants to visit the region peacefully, he should exert pressure on Israel to release the prisoners -- especially the ones who are on hunger strike -- or else he will visit while Palestine is on fire, " Minister of Prisoner Affairs Issa Qaraqe said.

CNN: Palestinians blame Israel for prisoner's death

"If President Obama wants to visit the region peacefully, he should exert pressure on Israel to release the prisoners -- especially the ones who are on hunger strike -- or else he will visit while Palestine is on fire, " Palestinian Minister of Prisoner Affairs Issa Qaraqe said.

CNN: Palestinians protest inmate's death, warn Obama

What had surprised me is that it doesn't seem like it's being discussed very much as to whether the U.S. should or should not release the women prisoners that the kidnappers are demanding be released.

NPR: The Morality of Negotiating with Kidnappers