SANDSPIT, B.C. - A mystery ship off the West Coast is believed to be carrying another load of migrants hoping to bypass immigration rules.

Tuesday, a navy ship with Immigration Canada officials aboard, was dispatched to intercept the ship, which is displaying no identification.

Officials didn't expect to intercept the ship, off the Queen Charlotte Islands, until Wednesday morning.

Authorities planned to warn the ship's captain about the consequences of entering Canadian jurisdiction illegally, and escort the ship to shore.

Those aboard the mystery ship know they're being watched. When it was spotted, the ship started travelling in circles instead of proceeding on its route toward B.C., said immigration spokesman George Varnai.

Three weeks ago, a similar vessel arrived in B.C. It was smuggling 123 Chinese nationals. After entering Canada illegally, they claimed refugee status.

National Defence says after the discovery of the first ship, it changed its surveillance of the West Coast. The new watch resulted in the discovery of the second ship on Monday.