The callers are demanding money to bail out the suspects arrested over the murder, reports add.
Speaking, police media spokesman - SP Ruwan Gunasekara said that the suspects would be produced before the Anuradhapura magistrate today.
Although it is said that over 20 have joined to murder the nightclub owner, only 08 have been arrested so far.
An Army deserter, who is said to be linked to the case too, is yet to be arrested.
Police add they have received much information after questioning the suspects.
Wasantha Zoysa was hacked to death by a group of masked persons who had entered a nightclub he owns in Muditha Mawatha, Anuradapura around 11.45 on Saturday night.
His funeral is to be held today.