Senior Congress leader P Chidambaram on Saturday said the detention of former Jammu and Kashmir Chief Minister Mehbooba Mufti was an abuse of law. Mufti’s detention under the Public Safety Act was on Friday extended by three more months.

Mufti is the only mainstream political leader of Jammu and Kashmir who remains detained under the stringent law. She has been in detention for nearly a year since the Centre scrapped Article 370 of the Constitution on August 5 to abrogate the region’s special status, and split it into the Union Territories of Jammu and Kashmir, and Ladakh.

In a series of tweets, Chidambaram said her detention was an assault on the Constitutional rights guaranteed to every citizen. He asked how a 61-year-old former chief minister, a protected person who is “under security guard round the clock”, could be a threat to public safety.

The stringent Public Safety Act has two sections – public order and threat to the security of the state. The former allows the accused to be detained without a trial for three months, a period that can be extended and the latter allows the accused to be detained for two years.

Chidambaram also supported Mufti’s decision to turn down an offer for her release on the condition that she will not speak against the abrogation of Article 370 and said any “self-respecting political leader” would refuse it. “One of the reasons given for her detention – the colour of her party’s flag – was laughable,” he added.

“Why should she undertake not to speak against the abrogation of Art 370?” he asked. “Is it not part of the right to free speech?” The former finance minister pointed out that he is one of the counsel appearing in the Supreme Court challenging the abrogation of Article 370. “[So,]If I speak against Article 370 – as I must – is that a threat to public safety?” he added. “We must collectively raise our voices and demand ‘Free Mehbooba Mufti immediately’.”

Almost all of the Kashmir Valley’s political leadership, including two other former chief ministers – Farooq Abdullah, his son Omar Abdullah – were locked up last year. Omar Abdullah was released seven months later on March 24 as the Jammu and Kashmir administration revoked his detention order under the Public Safety Act. Farooq Abdullah was released on March 13.

Last week, Mufti’s daughter, in an interview hit out at the Centre for its “cruel” detention of her mother and for stripping the region of its autonomy. “Luckily my mother has inner strength, but the whole point of putting her in isolation like that was very sinister, it was very cruel, it was to break her,” she said.