Update 11:50 a.m.: The suspicious package has been blown up.
Mike Veitenhans just told us (at 9:40 a.m.) that the bomb squad has closed off part of the trail around Green Lake because of a suspicious bag found on the trail.
The bomb squad has closed off the trail near the Bathhouse and the tennis courts on the west side and is using a robot to open the bag. Here’s the bomb squad truck and the robot in the left background.
Here’s the robot closeup.
And here’s the suspicious bag.
Thanks to Mike for the tip and all the photos.