JAKARTA (Reuters) - Indonesian search and rescue workers have a “strong indication” that an underwater sound they have heard is from the black box of a Lion Air passenger jet that crashed with 189 people on board this week, the country’s military chief said on Wednesday.

Military chief Hadi Tjahjanto told reporters that divers had already gone down to check the location, but were struggling with strong currents.

“We hope tonight we can drop anchor and release the ROV (remotely operated underwater vehicle) again and I am sure we will find a black box given the strong indication, and not far from there, the main body of the plane,” Tjahjanto said.