boroda, a couple of corrections-
1. I don't have a link to the us/china incident but if I remember correctly (And I'm fairly sure I do) the incident happened over international waters not Chinese air space. if it had been over Chinese airspace they would have used guns to bring the plane down.
2. I read the whole story in the link. And I basing this solely on the info you provided
nowhere does it say that anybody thought the ship was rammed intentionally. it says that the ship was suspected in a fatal collision, and excess crew members where removed from the ship so they would not interfere in the investigation, (or possibly destroy evidence or so the ship couldn't try to leave). No one was arrested until they tried to leave the country.
all these are perfectly reasonable actions when a vehicle is suspected in a fatal collision. Impounding a vehicle so it can be examined is standard in fatal accidents, even when the driver is not suspected to be at fault. securing evidence is reasonable and necessary for carrying out an investigation. and it's also reasonable to arrest someone for trying to leave the country while they are being investigated.
one more thing, it said the captain was being charged with manslaughter, so they apparently didn't think it was intentional. manslaughter is causing someone’s death through carelessness or neglect. murder is the charge when they think you did it on purpose.