The deceased has been identified as Deepak, an executive in a mobile SIM cards distribution company.
Police said the political affiliation of the victim was not immediately known. The state BJP said Deepak was an activist committed to "Hindutva ideology" and was associated with the Bajrang Dal and Vishwa Hindu Parishad in Dakshina Kannada district.
The assailants who came in a car stopped him while he was on his way to duty and attacked him with sharp weapons, police said.
The motive behind the killing, as well as the identity of the assailants was yet to be known, police said.
With this heinous killing, the number of Hindutva workers who have fallen to the 'murderous agenda of jehadi forces' has risen to 22, they said.
A series of killings of "Hindu activists" has often caused tension in the communally sensitive Dakshina district in the coastal region.
BJP has been accusing the Congress of adopting "a soft approach" towards "jehadi forces", a charge dismissed by the Siddaramaiah government, which has accused BJP of trying to polarise the situation.
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