Prajwal Revanna, who fled the country soon after a special investigation team was formed to probe the sexual abuse allegations against him, has become a major source of stress for the Congress government in Karnataka with no trace of the JDS MP who was expected to return from Germany early Thursday.

SIT officials were expecting Prajwal to arrive at the Bengaluru International Airport at 12.30am on Thursday from Munich but they had to return empty-handed as he didn’t board the flight.

After Karnataka voted for the Lok Sabha polls on April 26, Prajwal was expected to return to India via Bengaluru or Mangaluru airports. Prajwal and his father, Holenarasipura JDS MLA H.D. Revanna, are co-accused in a kidnap case registered by the son of a woman who had briefly worked at their house in Hassan.

Home minister G. Parameshwara requested former chief minister H.D. Kumaraswamy, the younger brother of Revanna, to reveal the identity of the “big shark” he has been talking about who has been involved in the revelations in pendrives, containing videos of purported sexual assault, found at various places.

“He knows there is a big shark. So isn’t it wrong not to disclose the details?” Parameshwara asked.

Kumaraswamy retorted that the SIT would unravel the big shark behind the pendrive episode if it did its job properly. “They can find out who the big shark is if they investigate properly. My question is whether they are investigating the case properly,” he told reporters.

With no trace of Prajwal, several writers and social activists wrote to chief minister Siddaramaiah seeking the immediate arrest of former Prime Minister H.D. Deve Gowda’s grandson.

Siddaramaiah has already written to Prime Minister Narendra Modi seeking cancellation of Prajwal’s diplomatic passport.