Marijuana is steadily infiltrating university campuses, sparking concern among administrators about how to stem growing drug abuse among students.

Scores of students at renowned universities, including Keio and Waseda in Tokyo, have been arrested this year for allegedly possessing or dealing the illegal drug.

Part of the reason, critics say, is that people feel less inhibited about getting their hands on marijuana than on other illegal drugs, such as amphetamines.

The critics also point to the relative ease with which cannabis seeds and information on how to grow the plants can be obtained on the Internet.

Waseda University said Nov. 17 that four of its students have been arrested since 2004 in violation of the Cannabis Control Law, in addition to three whose arrests were reported in early November.