The Associated Press

SEATTLE — Authorities evacuated dozens of workers and set up a half-mile perimeter around part of the city's port Wednesday after a bomb-sniffing dog indicated that two shipping containers from Pakistan could contain explosives.

By evening, no explosives had been found, and the port was preparing to resume normal operations, port spokesman David Schaefer said.

Customs agents used a gamma-ray device at Terminal 18 to peer through the containers' walls, and detected some items inside that did not match the containers' manifest, agency spokesman Mike Milne said.

The containers were checked by the bomb-sniffing dog, which reacted. A bomb squad searched the containers but found nothing dangerous.

Officials said the containers were supposed to contain oily rags, which are often shipped internationally for recycling or use in packaging.

It was not immediately clear why the dog indicated the presence of explosives.

Milne said the ship had originated in Hong Kong and made stops in China before arriving Monday in Seattle.

Terminal 18 covers nearly 200 acres. It serves more than 20 steamship lines and receives more than 40 vessels each month.