U.S. immigration officials found 18 illegal migrants inside a cargo container on a ship from Hong Kong Monday afternoon. Three of them were dead.

It's the third incident in the past two weeks at the Seattle port. But this is the first involving fatalities.

U.S. immigration says the survivors are in custody, but they were taken to a medical centre for emergency care.

"We have 15 Chinese men here, all showing signs of malnutrition and dehydration," said hospital spokesman Larry Zalin.

"So, we're giving them IV fluids, vitamins and running labs to see the extent of the care they'll need and whether they'll need to be admitted."

Since the new year, many groups of illegal immigrants have arrived in West Coast ports by hiding in canvas-covered containers:

  • 12 people caught Jan. 2 in Seattle
  • 25 people caught Jan. 4 in Vancouver
  • 14 people caught Jan. 5 in Seattle
Monday's ship, Cape May, and the one in Vancouver last week called California Jupiter are both owned by NYK, but officials say that doesn't mean the shipping line is involved with human smuggling.