Snow in East Boston park a matter of national security?

Adam Weiss reports he was ordered out of the Massport-owned Bremen Park yesterday by a Massport cop who singled him out, possibly because he was the only person there taking pictures - of the snow. Weiss said the cop told him the park was closed because of the snow, but that as he left - unsure at the time who actually had jurisdiction:

I couldn't help but notice all of the other people walking in the park, or the children playing in the snow, or the sign that gave the park's winter hours, and said nothing about it being closed in bad weather.