Greek police say they have destroyed a bomb planted outside a northern Athens bank, allegedly in solidarity with a convicted bank robber who has been on hunger strike for the past month because he wants to attend business school, the Associated Press reports.

Police said an anonymous caller alerted authorities to the timer-activated bomb, in the Aghia Paraskevi suburb, early Wednesday, Dec 10. Authorities cordoned off the area, and destroyed the device in a controlled explosion.

The caller, who gave a 30-minute warning, said the attack was in solidarity for Nikos Romanos, an anarchist, who has refused to take food since Nov 10 and is in an Athens hospital. On Wednesday, Romanos' lawyer said he was going to stop drinking too.

Authorities have rejected Romanos' bids to attend university classes.