Three men, purportedly former students of BN College, were caught drinking at the institute's hostel on Saturday afternoon, once again exposing chinks in the security measures taken by the Patna University administration.

Pirbahore police received a tip-off from the college hostel on Ashok Rajpath after the boarders complained that the outsiders were partying and had also beaten up students who opposed their activities.

Gautam Kumar, a resident of Naubatpur, and Jehanabad residents Saurav Kumar and Niraj Kumar were arrested while another in the group escaped from the scene.

The police said the four men were staying in the hostel illegally for months. "On Saturday we received information that some youths had organised a liquor party on the hostel campus," said Pirbahore police station house officer Qaiser Alam. "Three of them were arrested and booked under various sections of the prohibition act, and Indian Penal Code (relating to assault)."

"These outsiders are among those people who have graduated from the university long ago, but have stayed on in the hostels, occupying rooms," said one of the BN College hostel boarders on condition of anonymity for obvious reasons. "These youths live in the hostels free of cost, prepare for competitive examinations. Some of them are also political workers of different parties.

"As some of these outsiders living in the Patna University hostels are associated with different political parties, the police and district administration are also reluctant to take action against them," the student added.

BN College principal Rajkishore Prasad conceded that although the police and university administration conduct raids from time to time to evict unauthorised boarders, the outsiders come back after a few months. Students living in the hostel, however, allege that the raids are complete eyewash most of the time.

The arrest of the three inebriated men also expose security lapses on part of the BN College and Patna University administration in checking regular boarders at the hostels - which are more often than not known for all the wrong reasons.

Last week the Pirbhore police had raided the New Hostel of Patna College and caught an undergraduate student - a boarder of the hostel - with a sex worker in one of the hostel rooms. In February, a crude bomb had gone off at the same hostel as a second-year economics student showed juniors how to make the explosives.

Sources in the university said the hostel superintendents and wardens hardly conduct inspections at the hostels, giving outsiders enough scope to enter the buildings.

These outsiders, they said, are mostly former students who take up empty rooms in the hostels and often indulge in criminal activities such as extorting money from the students from rural areas in the name admission in colleges under Patna University.

"I have asked hostel superintendent D.N. Sinha to conduct an internal inquiry into this matter and submit a report to the college administration," said principal Rajkishore Prasad, adding that at the beginning of the academic session, hostel rooms are allotted to genuine boarders, but with time, former students occupy the rooms illegally.

Bihar National College, popularly known as BN College, was established in 1889 and is the second oldest college under Patna University after Patna College. It was once considered a premier institution.