UPDATE :
The US has carried out a submarine torpedo strike that sank an Iranian warship off the south coast of Sri Lanka, according to the US secretary of defence.
Pete Hegseth confirmed that the US was behind the deadly strike on an Iranian frigate that was travelling close to the Sri Lankan coast.
“An American submarine sunk an Iranian warship that thought it was safe in international waters,” Hegseth said. “Instead, it was sunk by a torpedo.”
US submarine sank Iranian warship off Sri Lanka’s coast, Hegseth says
Yeah, you can tell from the video that crew were mustering on deck. They had 0 knowledge they were under attack.