The Jammu and Kashmir administration has detained various leaders after the abrogation of Article 370 that granted special status to J&K.
Fayaz said that Jammu and Kashmir has seen a massive rise in the presence of armed forces and the severe curtailment of human rights.
In the letter, Fayaz wrote to Shah saying the detained leaders have been facing extremely poor living conditions.
"We strongly demand the release of all political leaders and party workers as well as the three former chief ministers who have been detained for more than three-and-a-half months now, and recently, when the detained leaders were being shifted to a new sub-jail, they were dealt with in a very humiliating manner," Fayaz said in the letter.
He also said that others who have been jailed over a period of three-and-a-half months and subsequently shifted outside Jammu and Kashmir also have the right to legal remedies and their conditions need immediate attention. They should be released and sent back, he added.
He said the MLA Hostel at the moment houses 33 detained political leaders, all coming from various political parties in Kashmir. To undertake the democratic process in Kashmir, the release of all jailed leaders is a pre-requisite, he added.
"We still believe that democracy is the most potent method to resolve these issues and differences that have created unrest among the people. Kashmir is facing a huge humanitarian and political crisis for 108 days now. There is fear, ambiguity and insecurity in the hearts and minds of people about their future," Fayaz said.
"The people of J&K have also been put through a very intense communication blackout, which was affected not only communication between people all over the Valley but has also affected the daily life. It is fundamental that the highest authorities within the government reach out to the people of Jammu and Kashmir and resolve their queries about the uncertainty and the consistent lockdown that they have been facing."
( With inputs from IANS )