Burmese authorities have released at least 20 student activists detained Friday in four cities and held overnight at undisclosed locations.

The students were detained in Rangoon, Mandalay, Lashio, and Shwebo late Friday, ahead of Saturday's 50th anniversary commemoration of the brutal suppression of a student movement. In 1962 the military bombed the Rangoon University student union building, killing dozens of students in an attempt to disperse students protesting the rise to power of authoritarian general Ne Win.

Burmese political activists called Friday's arrests “a misunderstanding” and called on the military-backed government to show greater confidence in student leaders.

A delegation from the Association of Southeast Asian Nations currently visiting Burma called the arrests an “act of oppression” that left the impression that “the old ways are still in effect” despite recent political reforms.

Among those arrested Friday was student leader Phyo Phyo Aung, a former political prisoner freed last year in an amnesty.

Students gathered at Rangoon University Saturday and said the arrests could dent the positive image of the 15-month-old government of Burma, also know as Myanmar.

The ASEAN Inter-Parliamentary Myanmar Caucus – AIPMC – also called on the government to release the students detained in Rangoon, Mandalay and other cities. AIPMC is in Burma on a fact-finding visit to assess the current reform process.