The arrest involves tax raids on DK Shivakumar in 2017. (File)

Senior Karnataka Congress leader DK Shivakumar was arrested last evening by the Enforcement Directorate with his supporters first trying to block officers from taking him away and later resorting to block traffic and vandalizing buses in protest. Mr Shivakumar, arrested after four days of questioning over money-laundering allegations, posted a tweet "congratulating" the ruling BJP for "finally" succeeding in arresting him.

Mr Shivakumar had been "uncooperative and evasive", the Enforcement Directorate said on his arrest. He was taken to hospital for a check-up, where doctors said his sugar levels were fluctuating. He will be produced in court today. The Congress has threatened protests across Karnataka.

The arrest involves tax raids on Mr Shivakumar in 2017, when Rs 8.6 crore in "undisclosed income" was allegedly found. The figure was revised to Rs 11 crore later.

Protests broke out in several parts of Karnataka following the arrest. Demonstrations and attempts to block roads by burning tyres were reported from Ramanagara, Chennapattana and a few neighboring towns, where a shutdown has been called for by Mr Shivakumar's supporters. As a precautionary measure, the district administration has declared holiday for schools and colleges today.

The Income Tax department accused Mr Shivakumar and his aide of transporting huge amounts of unaccounted cash on a regular basis through ''hawala'' channels with the help of three other accused. This was the time the Congress leader had arranged the stay at a Bengaluru resort of Gujarat Congress MLAs being sequestered before a Rajya Sabha election in which the party's Ahmed Patel was facing a tough challenge from the BJP.

In September last year, the Enforcement Directorate filed a money laundering case against Mr Shivakumar, based on a chargesheet filed by the Income Tax department.

The Congress has alleged political vendetta behind the action against Mr Shivakumar, the party's chief troubleshooter in Karnataka and at the forefront of efforts to keep the Congress-Janata Dal Secular coalition intact before an exodus of MLAs brought it down and led to the return of the BJP.

"DK Shivakumar, being the strong and obedient Congress leader in Karnataka, was always a target of the BJP," Congress general secretary KC Venugopal said in a statement.

Statement by General Secretary, AICC, Shri @kcvenugopalmp on the politically motivated arrest of Shri @DKShivakumarpic.twitter.com/bbcPJO1Cc0 — Congress (@INCIndia) September 4, 2019

Mr Shivakumar, accusing the BJP of targeting him, tweeted shortly after his arrest: "I congratulate my BJP friends for finally being successful in their mission of arresting me. The IT and ED cases against me are politically motivated and I am a victim of BJP's politics of vengeance and vendetta."

The 57-year-old Congress leader also assured the workers of the party and his supporters that he had not done anything illegal.

I congratulate my BJP friends for finally being successful in their mission of arresting me.



The IT and ED cases against me are politically motivated and I am a victim of BJP's politics of vengeance and vendetta. — DK Shivakumar (@DKShivakumar) September 3, 2019

A minister in the previous coalition government in Karnataka, Mr Shivakumar was summoned for questioning in Delhi on Thursday. The Enforcement Directorated acted after the Karnataka High Court refused to grant the Congress leader protection from arrest.

Karnataka Chief Minister BS Yediyurappa said he was "not happy" with the arrest of the rival politician. "Let me tell you one thing, the arrest of DK Shivakumar did not bring me any happiness. I will pray to God that he will be out soon," Mr Yediyurappa said.