One of the chlorine gas cylinders neutralised following a leakage at Sewri last week was found floating off the sea coast here, triggering panic in the area. Fire Brigade officials said on Thursday that the cylinder resurfaced off Worli coast in Central Mumbai last night. After over 120 people fell sick following the gas leakage at Mumbai Port Trust (MbPT) on July 14, the National Disaster Response Force (NDRF) and other experts had de-gased six chlorine gas cylinders at the port. Post neutralisation, two cylinders were disposed of in the deep sea, but one of them was found floating near the shore, they said. Police, Fire Brigade and NDRF personnel retrieved the cylinder. "It was an empty cylinder but as a precautionary measure, NDRF experts are examining it to ascertain if it contained any gas," a Fire Brigade official said.