Karti Chidambaram said he is surprised by the silence of civil society (File)

Lok Sabha MP Karti Chidambaram tweeted a letter on Saturday criticizing his father P Chidambaram's arrest by the government. He said that no investigative agency has been able to define the ''criminal act''.

He wrote that his father is being targeted for endorsing a decision taken by 12 government officers in his capacity as a minister.

"It's been a month since the CBI scaled the walls. Personal liberty has been denied in the pretext of a never-ending "investigation". Surprised by the silence of civil society. Schadenfreude. A crisis identifies true friends. Thankful for that. Truth and justice will prevail," he tweeted.

He added that the arrests of his father, Farooq Abdullah and DK Shivakumar is just a beginning of a long list to come.

P Chidambaram was arrested by the CBI on August 21. He is under judicial custody.

The 74-year-old is facing probe in cases registered by both the CBI and the Enforcement Directorate over alleged irregularities of a Foreign Investment Promotion Board clearance given to INX media in 2007.