Locals in Narsingdi's Monohardi upazila detained former Upazila Parishad chairman Saiful Islam Khan Biru on Thursday while he was buying a sacrificial cow at GangkulKandi Bhuiyan Bazar. Police took him to the station for safety following a call from residents. Biru, a five-time elected chairman and district Awami League adviser, had contested the last national election as an independent candidate. His detention triggered a protest by BNP leaders in front of the police station. Authorities say legal action is underway.