Madhuban Forensic centre will submit report on powerful blast in the relay box of the BSNL in Nahar House area close to a Police Post at Ambala late last night. The blast was so powerful that a wall of the Police post collapsed and two persons were injured. <br/><br/>The blast took place during a power shut down making people panic and started enquiring about the incident. <br/><br/>A spokesman of the police said that a team of Forensic Experts from Mahuban Police Training Centre Karnal visited the spot and took samples of the damaged relay box. <br/><br/>The cause of blast will be determined after receiving the report from Madhuban centre.