At around 11.30am, an anonymous caller identifying himself as a member of outlawed Sarbohara party told Prof Hossain over cell phone that somebody would go to his home soon to realize the toll.

The caller threatened the VC with death if he declines to pay the toll or informs police.

The VC filed a general diary with Motihar police station.

The caller told the VC that they need money to function as some of their leaders and activists were killed by law enforcers and many were arrested.

Talking to the The Daily Star, the VC said, he switched off his cell phone before the caller could tell anything about the amount of toll money.

Officer-in-Charge of Motihar police station Khandakar Ferdous Ahmed said, police have already started investigating the matter.

A number of RU teachers including a former pro VC were threatened either by outlaws or Islamist militants since 2005, but none of the culprits could be identified so far.