Bhupendra Yadav led the BJP delegation to Kannur which has witnessed clashes between the Left and BJP.
The BJP today alleged some 400 cases of assault on its activists in Kerala since the Left took power and demanded a probe either by the CBI or a high court judge.
"Ever since the Pinarayi Vijayan government assumed office four months ago, 400 cases of assault against our cadres by CPI-M supporters have taken place," BJP General Secretary Bhupendra Yadav said.
"We demand a probe either by the Central Bureau of Investigation or by a high court judge since justice from the state government is impossible," the Rajya Sabha MP said.
Mr Yadav led a delegation of Bharatiya Janata Party leaders who visited Kannur and other areas in Kerala for two days.
The team included Meenakshi Lekhi, NK Hegde and Nalinkumar Katteel as well as H Raja, the party secretary in charge of Kerala.
Mr Yadav claimed that violence against BJP cadres had happened in the Chief Minister's village as well.
The team members on Sunday called on Kerala Governor P Sathasivam and Home Secretary Nalini Netto and submitted an account of what it said was violence unleashed by the Communist Party of India-Marxist cadres.
"Three of our councillors have been killed in road accidents, 200 houses of our party members have been attacked... We do not expect to get justice under Vijayan," said Ms Lekhi.
Ms Lekhi gave a clean chit to BJP and Rashtriya Swayamsevak Sangh cadres for violence in Kannur.
Kerala Industries Minister EP Jayarajan told reporters in New Delhi that the BJP team's visit to the state was meant to please the RSS leaders and there was nothing else to it.