A device that looked like a bomb but was actually a homemade toy prompted authorities to close the ferry dock here for more than four hours Thursday, a Pierce County sheriff's spokesman said.

The device, which involved some plastic pipes taped together, was spotted jammed under a walkway leading to the dock at about 1:45 p.m.

Police used a remote-controlled robot to examine the item and determined shortly after 6 p.m. that it was not explosive, sheriff's spokesman Ed Troyer said.

Nearby children apparently made the toy and lost it in the water, Troyer said. One of the children's mothers brought her son down to the dock and he told investigators what had happened.

The toy apparently floated to the ferry dock and became stuck under the walkway, Troyer said.

Ferry and nearby railroad traffic was disrupted while the device was examined.

Burlington Northern Santa Fe spokesman Gus Melonas said eight trains were held back as a precaution.

Among the many people affected by the shutdown ferries were more than 200 workers at the Special Commitment Center for sex offenders on McNeil Island. They were stranded there after their shifts ended, Ron Van Boening, the center's chief administrator, told The News Tribune.