Nashik: A routine preparedness drill went awry when two stun grenades exploded within seconds, injuring four Ahilyanagar police personnel at the district police headquarters on Monday morning.The incident occurred around 9.30am during an exercise involving nearly 50 personnel from the Quick Response Team (QRT) and Riot Control Police ahead of Eid-al-Adha on May 27. Two policemen suffered hand injuries and were admitted to a private hospital, while two others sustained minor injuries.Superintendent of police Mummaka Sudarshan said, “An inquiry will be initiated into the case. In the event of any negligence, necessary action will be taken against the people responsible.” He added, “According to primary information, the personnel involved failed to follow necessary precautions while unpinning the stun grenades.”The police said that during the course of the exercise, one of the participants removed the safety pin of a stun grenade, but inadvertently released its lever, causing an immediate blast. Startled by the explosion, another officer dropped a second, already-unpinned grenade, leading to a second detonation and brief chaos at the site.Officials said even after removing the safety pin, the lever must remain firmly pressed and released only at the moment of throwing, as the device explodes within four to five seconds once released.Among the injured, Shubham Kavare and Yogesh Solunke have sustained cuts between their fingers and are likely to require stitches. Their wounds are likely to heal within three to four days. Shivraj Pawra suffered a minor facial injury due to flying debris, while Ganesh Madhe escaped with minor scratches.Reiterating the purpose of the devices, Sudarshan said, “Their sole objective is to create a thundering sound to disperse crowds.”The police added that the drill is a routine exercise being carried out across the district.