Sixteen busloads of out-of-town protesters are expected to arrive in Chicago on Thursday from Portland, Wa., and Los Angeles.

The first organized busload of protesters arrived in the city on Thursday from New York. The demonstrators described themselves as a peaceful and fun group. Most of them were staying at the Wellington United Church of Christ in the Lakeview neighborhood.

The first large NATO protest, permitted by the City of Chicago, is scheduled for Friday. So far this week, 12 people have been arrested.

Chicago Police Supt. Garry McCarthy tells WGN-TV he’s seen four separate and distinct groups of protesters so far. He estimates there were about 300 of them midweek, and expects about 10,000 by the time the Nato Summit gets underway at McCormick Place on Sunday.

Occupy Chicago and other groups say they hope to attract as many as 50,000 demonstrators. 

And while some groups say they’re here with a good message, other groups are protesting specific issues, such as foreclosures, economic policies, war and the NATO alliance.

Chicago police officers will be working 12-hour shifts throughout the weekend and on Monday, the second, and final day of the summit. 

McCarthy says while violence is a concern, the officers are very well trained and ready to keep the peace.