PETN explosive in UP Assembly: The Inspector General of Uttar Pradesh Anti-Terrorist Squad Aseem Arun today hinted at a possible terrorist activity as PETN explosive was found lying under the seat of a Samajwadi Party MLA inside the UP Assembly. "Anti Terrorist Squad will do a detailed investigation of the spot today and we will scan through CCTV footage," Arun said as per ANI. The news agency also reported that an FIR was also registered against unknown persons in connection with explosive material found in the Assembly. The PETN, one of the most dangerous plastic explosives, is available in the black market and it can easily pass through security checks, as per PTI. The explosive packet of about 150 grams was found close to the seat of Leader of the Opposition Ram Govind Chaudhary, which is close to the podium where the Speaker sits, the report added. Chief Minister Yogi Adityanath while addressing the shocked Assembly said, "This is PETN (Pentaerythritol Tetranitrate), this is a dangerous substance," He added. Experts say that 500 gm of this explosive can blow up the House. The explosive was found by the cleaning staff on July 12. The dog squad failed to detect it, the chief minister said, as per PTI. Earlier in the day, the UP CM demanded an NIA investigation into the matter, while asking, "how can we allow one individual to play with the safety of 503 MLAs?" Many countries across the globe have severe restrictions on the purchase of PETN which can be bought in powder form or thin plastic sheets, the report said. Military uses the substance legally and also it is used by mining industries. The PTI report says, it is believed that PETN explosives have been used in the 2011 Delhi High Court blast, which killed atleast 17 people.