"Suraj was booked under the Indian Penal Code section 306 of Indian Penal Code and placed under arrest in connection with Jiah Khan suicide case," Additional Police Commissioner Vishwas Nangre Patil said.
Suraj, 21, will be produced before a court on Tuesday.
The six-page note written by the 25-year-old actress who hanged herself at her Juhu residence last Monday, throws light on the rocky relationship between the two. Jiah's mother Rabia Khan has alleged that her daughter suffered 'trauma and abuse' at the hands of her lover and his father.
The note, meant for Suraj and discovered three days after Jiah's death, has revealed that the actress was 'deeply hurt' as she had to abort her baby with Suraj.
Jiah's distraught mother Rabiya Khan on Monday broke her silence and claimed her daughter ended life due to "trauma and abuse" caused by Suraj and his actor father Aditya.
Rabiya also rubbished media reports that a floundering career forced Jiah to end her life.
Rabiya tweeted "I am convinced that either Suraj or Aditya has hit my daughter and it's that humiliation which triggered her death."
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