NEW YORK — A gas main leak has been found at the site of the explosion that killed eight people and leveled two Manhattan buildings, federal investigators said Tuesday but cautioned that they are still a long way from determining what caused the blast.
The leaking gas main was adjacent to 1646 Park Ave., one of the buildings destroyed in the March 12 blast, the National Transportation Safety Board said.
According to the NTSB, the leak was detected during a pressure test on the 8-inch main beneath Park Avenue. A tracer gas escaped under normal operating pressure, investigators said.
Authorities have said the blast erupted about 15 minutes after someone from a neighboring building reported smelling gas. And the NTSB said Friday that underground tests conducted in the hours after the explosion registered high concentrations of natural gas.
However, board spokesman Eric Weiss said investigators were far from deciding what caused the explosion. ‘‘We don’t determine the probable cause until the very, very end.”