(Adds further comment from Warren, comment from Afghan government, paragraphs, 4-8)
WASHINGTON, Jan 27 (Reuters) - The United States warned the Afghan government on Monday against releasing prisoners that Washington says should be tried as dangerous militants, the latest dispute to inflame U.S.-Afghan relations.
Colonel Steve Warren, a Pentagon spokesman, said the Afghan government had directed the Afghan Review Board, a government body, to release 37 detainees, but Warren said some were linked to production of or attacks using improvised bombs, while others were believed to have been involved in attacks on Afghan or foreign soldiers.
"These are bad guys. These are individuals with blood on their hands, both U.S., coalition and Afghan blood on their hands," Warren told reporters at the Pentagon.
He said authorities had "strong evidence" that would support prosecution of some prisoners, and leads on other prisoners that justified further investigation.
The prisoners' fate is the latest issue to trouble relations between Washington and Kabul as the Obama administration presses Afghan President Hamid Karzai to sign a security pact that would authorize U.S. troops to remain in Afghanistan after 2014.
In recent days Karzai has appeared to stiffen his resolve not to sign the pact, saying the United States should leave Afghanistan if it cannot restart peace talks with the Taliban.
A spokesman for Karzai said that "condemning the decision of Afghan judicial authorities is a clear breach of Afghan sovereignty."
"The release of innocent Afghan detainees from Bagram prison is the decision of our judicial authorities, taken in a judicial meeting sometime back, and it has to be respected and put in action as soon as possible," the spokesman said.
Warren said the U.S. government had formally disputed the release, but the 37 prisoners, part of a larger group of 88 under dispute, were now 'in the release process.'
"There are a few other steps that are required inside of the Afghan system before they are actually freed," he said.
NATO Secretary-General Anders Fogh Rasmussen also said he would be concerned if the prisoners were released for political reasons. (Reporting By David Alexander and Missy Ryan and Doina Chiacu; Editing by Grant McCool and David Gregorio)