Little less than a year is all it took for illegal boarders and violence to return to Saidpur hostel as students claimed illegal boarders were preparing bombs to seek revenge on another group.

Police on Sunday recovered five live bombs and a large quantity of bomb-making materials from the hostel.

The senior superintendent of police said the explosives had been stored for carrying out campus violence.

On Monday, a student leader at Patna University said revenge was on the minds of some people living illegally at Saidpur hostel, and they planned to explode bombs at Darbhanga House which houses the university's postgraduate departments.

The trigger was a clash on the campus between students a couple of weeks back.

"A fortnight ago, a group of youths from Saidpur hostel were beaten up at Darbhanga House over eve-teasing," said Sumant Kumar, the student leader. Patna College hostel boarders had beaten up the alleged eve-teasers. Had the Saidpur boarders been successful in their plan, it would have triggered campus violence as both the groups are from different castes. It would have led to tension on the university campus."

The cluster of Saidpur hostels has gained notoriety over the years for allegedly nurturing criminals. There are nine hostel blocks but only three of them are habitable. Illegal boarders occupying the hostels were evicted last year based on a Patna High Court directive. After removing the encroachers, the university conducted a hostel allotment for postgraduate students in blocks 1, 6 and 9.

Within 10 months, the encroachers have returned, surprising even the Patna University administration.

"This year there has been no fresh allotment for hostels - the university has no record of it," said university proctor G.K. Pillai.

However, sources said a major chunk of the illegal boarders were outsiders who re-entered the hostel last year.

As none of the Saidpur hostels have boundary walls and there is minimal security measures, outsiders find it easy to enter the hostel blocks.

Superintendent of Saidpur hostel no. 6 and Patna Science College teacher Shardendu said that it is difficult to check illegal boarders at Saidpur hostel. He said: "Last year the university carried out an allotment process, giving rooms to postgraduate students but in some time, many illegal boarders entered the campus."

He added that most teachers stayed away from taking the responsibility of Saidpur hostel because of the challenges in managing its affairs in the face of frequent trouble and violence.