In an open letter to the Syrian National Council, released Tuesday, Human Rights Watch (HRW), detailed allegations of kidnapping for ransom, detention, and torture of security force members and government supporters.

HRW's Middle East director, Sarah Leah Whitson, said,

"The Syrian government's brutal tactics cannot justify abuses by armed opposition groups,"

"Opposition leaders should make it clear to their followers that they must not torture, kidnap, or execute under any circumstances."

Extracts reproduced below:

"We recognize that the perpetrators of these abuses are not always easy to identify nor do they necessarily belong to an organized command structure that follows the orders of the SNC or other opposition groups. Some reports received by Human Rights Watch indicate that in addition to armed groups with political motivations, criminal gangs, sometimes operating in the name of the opposition, may be carrying out some of these crimes."

"Following the creation of the SNC Military Bureau on March 1, 2012, to liaise with, unify, and supervise armed opposition groups including the Free Syrian Army (FSA), Human Rights Watch calls on the Bureau to condemn and forbid these abuses in order to achieve its objective of ensuring members of the armed opposition comply with international humanitarian law and to meet its human rights obligations. Human Rights Watch also calls on members of the armed opposition that are not under the operational command of the SNC to desist from committing these rights abuses."