MINNEAPOLIS -- Police have arrested 16 people for crossing the collapse site perimeter near the Interstate 35W bridge.

Two people were arrested on Tuesday, authorities said.

As reported by the Star Tribune, the new perimeter is being secured by fences at least 8 feet high, and motion detectors and cameras will allow police to monitor the scene using the city's Wireless Minneapolis network.

The citywide wireless network won't be operational until the end of 2007, when it will become available to all Minneapolis residents and businesses. Still, emergency responders were able to use the network to share information during and after the collapse.

Sending digital maps increased efficient transportation onsite during the rescue efforts. Now, 24-hour surveillance helps police keep an eye on the site perimeter and keep intruders away from potentially dangerous debris.

Wireless cameras on the 10th Avenue Bridge overlook the I-35W bridge, and provide live views of the site to emergency planners and workers in the Emergency Operations Center and Incident Command Centers.

The cameras are also used to track the progress of the recovery operations.