The Congress has been targeting the ruling BJP following the incident.
Karnataka BJP president Nalin Kumar Kateel on Tuesday said he will seek an explanation from party leaders, who shared the stage with rowdy-sheeter 'Silent' Sunil and made it clear that he will not be inducted into the party at any cost.
BJP's Bangalore Central MP P C Mohan, Bangalore South MP Tejasvi Surya, Chickpet MLA Uday Garudahar, Bengaluru South BJP president N R Ramesh among others on Sunday were seen at a blood donation camp with Sunil, which sparked a controversy in some quarters.
It had also given rise to speculation that Sunil would join the BJP to make his political debut.
"'Silent' Sunil will not be inducted into the party at any cost. I'm gathering information about some party leaders participating in an event along with him. An explanation will be sought from those leaders," Mr Kateel said.
In a statement, he said he has directed leaders to see to it that such incidents don't repeat and has asked them to bring all matters to the party's notice.
"The party will never tolerate terrorists, those supporting terror activities and those with criminal background," he added.
Sunil, who was once considered among Bengaluru's most feared alleged contract killers, now claims to have shunned criminal activities and taken up the task of serving society.
The Congress has been targeting the ruling BJP following the incident.
AICC General Secretary in-charge of Karnataka Randeep Singh Surjewala in a tweet said, "BJP's recipe for Bangaloreans' Rowdy sheeters, who can't be found in raid by police are found with BJP leaders on public platform, joining politics AND inspired by Modi. Those involved in betting in the past, now also inspired by BJP and Modi."
State Congress President D K Shivakumar, Leader of the Opposition Siddaramaiah too have hit out at the BJP government.
Hitting back at the Congress, BJP in a tweet claimed Mr Shivakumar was once "favourite disciple" of gangster Kotwal Ramachandra.
"Once the Kotwal's favorite disciple! Promoted to the post of Karnataka Congress State President from Tihar Jail. Have you forgotten 'those days' of your party's state president?
"Raised in the underworld D K Shivakumar is the Congress President. Murder accused Vinay Kulkarni and Mohammad Nalapad known for goondaism are Karnataka Congress leaders...," it added.
Reacting to Congress' attack on BJP, Chief Minister Basavaraj Bommai in New Delhi asked the grand old party to "count" the number of rowdy-sheeters it has.
Police too had come under the scrutiny, following Sunday's event, as Sunil was reportedly not available to the police when they had recently conducted raids on rowdy-sheeters in Bengaluru.
Clarifying that there is no political pressure on the police, Central Crime Branch (CCB) Joint Commissioner S D Sharanappa on Monday said there was no pending warrant against Sunil, nor is the person needed for inquiry in connection with any case; so he was not picked up from the venue after the event immediately.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)