LYNN – A grenade was found inside a basement wall in Lynn on Tuesday afternoon, police said.A contractor from the local housing authority was working on weatherization at 37 Lake Ave., near Flax Pond, when a grenade was found inside the wall of a two-family home.”It had been there for a number of years,” Police Lt. William Sharpe said.State Police responded around 4 p.m. and took the grenade to be destroyed. The home was evacuated as a precaution and an ambulance was placed on standby, but there were no reported injuries.