Authorities evacuated dozens of workers and set up a half-mile perimeter around part of the city's port after a bomb-sniffing dog indicated that two shipping containers from Pakistan could contain explosives. By early evening Wednesday there was no sign of explosives and the port was preparing to resume normal operations, port spokesman David Schaefer said. Customs agents used a "gamma-ray" device at Terminal 18, south of downtown, to peer through the containers' steel walls and detected some items inside did not match the containers' manifest, agency spokesman Mike Milne said. The containers were checked by the bomb-sniffing dog. The dog reacted, but a bomb squad that searched the containers found nothing dangerous.