Metropolitan Magistrate Sudesh Kumar convicted them for rioting and obstructing police from discharging its duty after they pleaded guilty.
Those found guilty also included 11 students who were protesting with others against Chinese government for implementation of the basic human rights of Tibetans.
Besides imposing the day-long detention, the court also sentenced them to three days in prison, but set it off against the imprisonment which they already had served after their arrest in 2008 during demonstration.
The court also imposed a fine of Rs 1,000 on each of the convicts.
"They (convicts) were fighting and protesting against Chinese government for the implementation of the basic human rights to the Tibetans," the court said.
The magistrate while framing charges against them said that on March 3, 2008, they had formed unlawful assembly in front of the China Embassy in Chanakya Puri here with a common intention and committed the offence of "rioting".
"You all (accused) voluntarily obstructed policeman, public servant, in discharge of his public duties and in disobedience of the directions of the order duly promulgated by him and thereby committed offence under section 186/188 (obstructing public servant in discharge of public functions) of the IPC," the court said.
