Police say the annual Halloween block party that helped earn Ohio University its No. 1 party school ranking ended this year with 50 arrests, largely alcohol related.

The Saturday night party near the university in downtown Athens generally draws about 20,000 people, and authorities say this year's crowd was typical. They say ambulance calls were up -- to about 45 -- and were mostly alcohol related.

Revelers interviewed by The Athens Messenger say they felt comfortable with the security level and called the event safe and fun.

Arrests in some recent years have eclipsed 200. The university was voted the top party school in August on the 2011 Princeton Review surveys.

Security has been beefed up since 2003, when partygoers rioted.

The event is not sanctioned by the university.