HYDERABAD: Tension prevailed for some time in Nampally on Wednesday after members of tribal student unions led by TRS leader G Srinivas attempted to lay siege to the at BJP party office demanding 12 per cent reservation for STs. BJP Yuva Morcha activists present there raised slogans of ‘KCR down down.’ Police stationed there laid barricades to prevent the two groups from clashing and took the protesting students into custody.