Meerut, Sept. 27 -- Sambhal police on Thursday night arrested the key accused in the brutal acid attack on a 22-year-old teacher following an exchange of fire late on Thursday night, they said. The accused, identified as Nishu from Amroha district, was injured in the leg during the crossfire and admitted to the district hospital. According to officials, Nishu fired at police with a country-made weapon during a checking drive on the Asmoli-Kalyanpur road around 10.30 pm. In retaliatory firing, he was shot in the leg. Police recovered the scooter used in the acid attack, along with the pistol and two empty cartridges. Additional SP (North) Kuldeep Singh and Asmoli CO Kuldeep Singh inspected the spot after the encounter. "The accused is undergoing treatment and will be interrogated further once his health stabilises," SP Krishan Kumar Bishnoi said. He added that police teams had been pursuing Nishu for the last two days. The 22-year-old woman, who teaches at a private inter-college, suffered 30 per cent burns after the attackers splashed acid on her face and abdomen near Kalyanpur village of Sambhal on Tuesday afternoon. She has been admitted to AIIMS, Delhi, where her condition was said to be critical. An investigation revealed that Nishu had worked at a chemist's shop two years ago, where he managed to take some acid secretly. That same acid was used in the attack, police said....